A graduate of Williams College, Marash worked at New Brunswick, New Jersey station WCTC-AM (1450), where he hosted a nightly talk show, Dave Marash On Call. He had also been a reporter at WPIX. He subsequently worked at WCBS-TV in New York.
Marash was host of ESPN's Baseball Tonight and NBC's GrandStand, which alternated as a National Football League pregame show or a sports anthology series, depending on the season. In the early years of the Fox television network, Marash hosted a magazine-style show of science and technology entitled Beyond Tomorrow.
He then worked at ABC News. His last appearance prior to joining Al Jazeera English was on Nightline. He had anchored newscasts at WNBC in New York and WRC-TV in Washington, D.C. during the mid-1980s. He received Emmy Awards for his Nightline coverage of the Oklahoma City bombing and for his coverage of the explosion of TWA Flight 800. His May 2001 Nightline documentary about singer Eva Cassidy was one of the highlights of his years with the program.
Marash garnered considerable attention when he joined Al Jazeera English in January 2006 as the network's Washington, D.C. anchor, thus becoming the de facto American face of the new English-language station. Two years later, in March 2008, he stepped down from his position. Marash explained, "To put it bluntly, the channel that's on now — while excellent, and I plan to be a lifetime viewer — is not the channel that I signed up to do." Specifically, he cited the loss of editorial control and his inability to vouch for content that the network was broadcasting, as reasons for his departure.
On February 14, 2011, Marash defended Al Jazeera English on the O'Reilly Factor on Fox News against claims by Bill O'Reilly that Al Jazeera was anti-American. He joined Santa Fe, New Mexico public radio station KSFR-FM 101.1 in March of 2014 as co-News Director. Since September 2014, he has hosted HERE AND THERE, a 4-times-weekly series of 50 minute news interviews.
- Nightline Daily Email: 7/2 Leroy Sievers; retrieved March 6, 2008.
- Marash Joins Jazeera: "Marriage Made in Heaven", The New York Observer, January 12, 2006, accessed May 2, 2008
- American Anchor Quits Al Jazeera English Channel, The New York Times, March 28, 2008; accessed April 13, 2008
- "Dave Marash: Why I Quit", Columbia Journalism Review - The Water Cooler, April 4, 2008, accessed April 13, 2008
- Nox Solutions (2011-02-14). "Bill O'Reilly: The O'Reilly Factor - Monday, February 14, 2011". Billoreilly.com. Retrieved 2011-11-14.
- George Weston (2014-03-06). "Award-Winning Journalists to Lead KSFR's News Team". ksfr.org. Retrieved 2011-03-26.
- "Hope for the Hirsute", time.com, July 6, 1970; accessed October 17, 2014.
- Profile, msnbc.msn.com; accessed October 17, 2014.
- "In Defense of 'Self-Hating' Jews" by Menachem Wecker, Jewish Currents, May 2007, which quotes Marash