Israel–Lebanon relations have never existed under normal economic or diplomatic conditions, but Lebanon was the first Arab league nation to signal a desire for an armistice treaty with Israel in 1949. Lebanon did not participate in the 1967 or 1973 wars in any significant way, and until the early 1970s Lebanon's border with Israel was the calmest frontier between Israel and any of the other adjacent Arab League states.
The two countries are full members of the Union for the Mediterranean and many other international organizations.
The armistice agreement between Lebanon and Israel was relatively straightforward. Unlike the other armistice agreements, there was no clause disclaiming the Blue Line as the international border between Lebanon and the former Palestine; it continued to be treated as the de jure international border. As a result, Israeli forces withdrew from 13 Lebanese villages it had seized during offensive operations in October 1948.
Unlike other Arab states, the Jewish population of Lebanon grew after the 1948 founding of the State of Israel.
Lebanese Civil War
Some right-wing militias were Israel's allies in the Lebanese Civil War. After the PLO was ejected from Beirut in the summer of 1982, Lebanese President Bashir Gemayel flew to the Israeli coastal town of Nahariya to talk with Menachem Begin and Ariel Sharon. Begin and Sharon proposed that Israel and Lebanon establish full diplomatic relations, but Gemayel proposed a kind of formal non-aggression pact. When Sharon reminded Gemayel that Israel controlled most of Lebanon at that time and that it would be wise to follow Israel's instructions Gemayel held out his hands and replied "Put the handcuffs on.... I am not your vassal." Gemayel left Israel without making any formal agreement and he was assassinated two weeks later by Syrian nationalists.
After the assassination of Gemayel, Israel and Lebanon signed an agreement on May 17, 1983 which was a peace treaty in all but name. Lebanon signed the agreement under American and Israeli pressure, but it was opposed by Syria. The agreement was conditional on Syrian withdrawal, which did not occur until April 2005. Much of the content of the treaty was contained in secret protocols and memoranda, and it did not win expected Jordanian and Saudi endorsement. The Lebanese legislature ratified the treaty by a margin of 80 votes, but in a very weak and unstable domestic position President Amin Gemayel abrogated the peace treaty on March 5, 1984. under unrelenting Syrian pressure, after the US Marines withdrew and after Israel had begun withdrawing from Lebanon.
The success of the First Persian Gulf War created new opportunities for Middle East peacemaking. In October 1991, under the sponsorship of the United States and the then Soviet Union, Middle East peace talks were held in Madrid, Spain, where Israel and a majority of its Arab neighbors conducted direct bilateral negotiations to seek a just, lasting, and comprehensive peace based on UN Security Council Resolutions 242 and 338 (and 425 on Lebanon) and the concept of "land for peace." Lebanon, Jordan, Syria, and representatives of the Palestinians continued negotiating until the Oslo interim peace accords were concluded between Israel and the Palestinians in September 1993 and Jordan and Israel signed an agreement in October 1994. In March 1996, Syria and Israel held another round of Madrid talks; the Lebanon track did not reconvene.
In early April 1996, Israel conducted its military operation "Grapes of Wrath" in response to Hezbollah's actions on Israeli military bases in south Lebanon. The 16-day operation caused hundreds of thousands of civilians in south Lebanon to flee their homes. On April 18, several Israeli shells struck refugee compounds, killing 102 civilians sheltered there.
Throughout the 1990s discontent had been growing in Israel about the occupation of parts of Lebanon. Discontent increased as a result of a 1997 helicopter crash that killed 73 Israeli soldiers bound for Lebanon. Ehud Barak campaigned for prime minister on a platform of withdrawing from Lebanon. On June 28, 1999 Farid Abboud, the Lebanese ambassador to the USA, addressed the Los Angeles World Affairs Council to give an update on the peace process. Finally, on May 23, 2000, the Israeli military carried out a withdrawal of Israeli troops from the south and the Bekaa valley, effectively ending 22 years of occupation. The SLA collapsed and about 6,000 SLA members and their families fled the country, although more than 2,200 had returned by December 2001. With the withdrawal of Israeli forces, many in Lebanon began calling for a review of the continued presence of Syrian troops, estimated in late 2001 at approximately 25,000.
On June 16, 2000, the UN Security Council adopted the report of the Secretary General verifying Israeli compliance with UNSCR 425 and the withdrawal of Israeli troops to their side of the demarcated Lebanese-Israeli line of separation (the "Blue Line") mapped out by UN cartographers. (The international border between Lebanon and Israel is still to be determined in the framework of a peace agreement.) In August, the Government of Lebanon deployed over 1,000 police and soldiers to the former security zone, but Hezbollah also maintained observation posts and conducted patrols along the Blue Line. While Lebanon and Syria agreed to respect the Blue Line, both have registered objections and continue to argue that Israel has not fully withdrawn from Lebanese soil. As regional tension escalated with the Palestinian intifada in September 2000, Hezbollah cited Blue Line discrepancies when it reengaged Israel on October 7, taking three Israeli soldiers captive in an area known as Shebaa Farms. This largely unpopulated Israeli controlled territory along the border between Lebanon and Syria is claimed by Lebanon, although the United Nations and most of the world community, including Israel, agree that Shebaa Farms is part of Syria. Hezbollah sought to use the captives for leverage to release Lebanese prisoners.
Since the beginning of the Cedar Revolution, hopes had increased of an Israel-Lebanon peace treaty. In a May 2005 Newsweek interview Saad Hariri said "We would like to have peace with Israel. We don't want wars. We hope that the peace process moves ahead with us, with the Syrians, with all the Arab countries," but he added that Lebanon would not sign a separate peace treaty as Jordan and Egypt have done. Other Lebanese leaders draw an even harder line.
2006 Lebanon War
Lebanese Prime Minister Fouad Siniora said in August 2006 that Lebanon would be the "last Arab country to make peace with Israel" because of the large number of civilians that were killed in the 2006 Lebanon War. Sheikh Hassan Nasrallah, the leader of Hezbollah, proclaims "Death to Israel" and promises the "liberation" of Jerusalem. It is highly unlikely that Lebanon will sign a peace treaty with Israel before Syria, as Syria's influence on Lebanese politics is still strong.
It was uncovered in the cache of diplomatic cables released by Wikileaks that in 2008, Lebanese Defense Minister had sent messages to Israel via the United States stating the Lebanese Army would refrain from getting involved in a future conflict between Israel and Hezbollah and that the army, as quoted in the cables "will move to pre-position food, money, and water with these units so they can stay on their bases when Israel comes for Hezbollah — discreetly, Murr added." Additionally, he advised Israel to ensure not to "bomb bridges and infrastructure in the Christian areas." According to former U.S. Ambassador to Lebanon Michele Sison, the dispatcher of the cable, "Murr offered some ideas aimed at avoiding turning the Christian population against Israel when the next war with Hezbollah occurs . . . Murr also outlined his orders to the Lebanese Army when/if Israel invades to counter Hezbollah."
Since April 2009 Lebanese authorities have arrested almost 100 people suspected of spying on behalf of Israel. Many are expected to receive the death penalty which the Lebanese cabinet has announced it intends to carry out.
Natural Gas dispute
In 2010, Israel discovered massive deposits of natural gas off its coast in the Mediterranean Sea. While Israel's find is within its territorial exclusive economic zone, the dispute stems from the possibility that the gas field spans to Lebanon's boundary. A general principle in such a situation is the Rule of capture where each side is permitted to lift as much as it can on its side. Israel has already started exploration and construction on its side, while Lebanese authorities have not yet officially demarcated its exclusive economic zone or initiated a process of attracting bids for exploration rights.  Lebanese Energy Minister Gebran Basil warned that Lebanon would not allow Israel or any company "serving Israeli interests" to drill gas "that is in our territory". Beirut had previously warned the American Noble Energy company not to approach its territory. In response, Israeli Infrastructure Minister Uzi Landau warned Lebanon that Israel was willing to use force to protect the gas reserves discovered off its shores.
On 17 August, the Parliament of Lebanon passed authorising exploration and drilling of offshore oil and gas fields. The law called for the establishment of a treasury and a committee to oversee exploration and drilling. Speaker Nabih Berri's advisor, Ali Hamdan, said that he expected rights to be up for auction by the end of 2011. "This is definitely a major cornerstone in Lebanon's oil policy... and will help Lebanon divide its reserves into blocks an eventually bring in tenders and start looking into power-sharing agreements."
2010 border clash
On August 3, 2010, a clash took place near the Lebanese border village of Adaisseh between the Israel Defense Forces and Lebanese Armed Forces after an Israeli patrol operating on the border clashed with Lebanese troops. Israel claimed that the troops had stayed within Israel, while Lebanon claimed that the soldiers had crossed the border to uproot trees. An ensuing firefight resulted in the deaths of three Lebanese soldiers and one senior Israeli commander; two Israeli soldiers and five Lebanese soldiers were also wounded. A Lebanese journalist was also killed. Israeli artillery and helicopter gunships then struck several Lebanese Army posts and the Lebanese Army's southern headquarters, destroying several military vehicles.
- Lebanon Israel Armistice Agreement UN Doc S/1296 23 March 1949
- "Israeli-Lebanon Armistice Agreement". Jewish Virtual Library. Retrieved 2012-11-15.
- Shlaim, Avi (2001). The Iron Wall: Israel and the Arab World. W.W. Norton & Company. p. 415. ISBN 0-393-32112-6.
- Farid Abboud: Peace Process
- Report of the Secretary-General on the implementation of Security Council resolutions 425 (1978) and 426 (1978), May 22, 2000.
- Hatoum, Leila (2006-08-31). "Siniora vows to be last in making peace with Israel". The Daily Star (Lebanon). Retrieved 2012-11-15.
- Daragahi, Borzou; Lutz, Meris (December 3, 2010). "Lebanon defense chief worked with U.S. against Hezbollah, leaked cable says". Los Angeles Times.
- "Lebanon busts 2nd Mossad telecom spy". Tehran, Iran: Press TV. July 28, 2010. Archived from the original on July 29, 2010. Retrieved July 29, 2010.
- Israel-Lebanon Offshore Oil & Gas Dispute – Rules of International Maritime Law Martin Waehlisch, ASIL Insight (American Society of International Law), Vol. 15, Issue 3, Dec. 5, 2011.