"Be careful how you use it" 
Hai Karate is best remembered today for its marketing plan, with a small self-defense instruction booklet sold with each bottle (to help wearers fend off women) and its television adverts. In the UK spots, a stereotypical nerd covers himself in Hai Karate and is promptly seduced by a female passer-by played by British starlet Valerie Leon; similar ads ran in the US as well. All of the spots contained the catch phrase "Be careful how you use it".
The fragrance was developed by the Leeming division of Pfizer and launched in 1967. As well as the original Hai Karate fragrance, versions named Oriental Lime and Oriental Spice were soon introduced. It competed successfully with such other brands as Aqua Velva, Old Spice, Jaguar, Dante and Brut before fading away in the 1980s.
Pop culture references 
- It was used by the Sussex Thunder British American football team as part of their pre-game "musking up" superstition before the 2012 Britbowl. It was purchased via eBay.
- Nedley Mandingo from the Bubba the Love Sponge Show admitted to still using Hai Karate on the October 19, 2009 show. His supply is purchased via eBay.
- Samuel L. Jackson's character Frozone in the The Incredibles splashes on Hai Karate. 
- William Bennett's morning political talk show Morning in America featured several segments where Seth, one of Bennett's assistants on the show, went in search of a bottle of the scent. Bennett gave Seth a bottle for Christmas of 2006 after finding it in a relative's old things. The bottle is considered part of the studio's shared collection and is occasionally referred to in great reverence.
- In "A Night to Remember" episode 318 of Dharma & Greg, Dharma's dad uses a vial of Hai Karate to help jog his memory.
- In the stoner movie Puff, Puff, Pass starring Danny Masterson and Ronnie Warner, Masterson's character questions Warner about his aftershave, asking if it was Hai Karate. He then asks where Warner found Hai Karate, getting the response "Ebay".
- In "Bubba Hyde", Diamond Rio's 1994 country hit, the lyrics mention Bubba Hyde, the song's protagonist, "slaps on his Hai Karate aftershave" before heading out to the Honky Tonk.
- In Dean Koontz novel, From the Corner of His Eye, the killer, Junior Cain, splashes a little Hai Karate behind each ear before attempting to seduce a nurse he met in the hospital. (Page 211.)
- In a Married... with Children episode, "Spring Break (Part 2)", Al, Jefferson and Griff are wearing Hai Karate while crashing spring break in Fort Lauderdale, Florida. The girls in Fort Lauderdale refer to it as "Geezer" smell.
- In another Married... with Children episode, "Ride Scare", one of the fat women Al is carpooling with asks him " So do you always go to work wearing a suit and smelling of Hai Karate?:
- In the Disney Channel original movie Under Wraps Hai Karate is mentioned in two scenes in the movie.
- In the episode "Grandpa's Visit" of the seventies sitcom Good Times, J.J. tells his brother Michael to look in the medicine cabinet "next to his Hai Karate and his Clearasil".
- In Will & Grace Season 2 disc 4, Will mentions the product in reference to a co-worker.
- In the fifth episode of the first series of Life on Mars (UK), a scarf belonging to a suspect is said to smell like Hai Karate by Chris Skelton.
- Ray Carling also says he's "a black belt in Hai Karate" in the Ashes to Ashes 2010 Sports Relief special.
- Hai Karate is referenced by Ray Carling once again in the fourth episode of the final series of Ashes to Ashes when he comments to Chris Skelton that he should "go easy on that Hai Karate". Skelton responds by telling Carling "it's just a dab and a dash".
- Hai Karate was a grunge/punk band that was on Frank Kozik's now defunct Man's Ruin Records. One of its members, bassist Bob Blackstone, was in the Seattle garage rockers Gas Huffer. Hai Karate released one self-titled full length album (in 1998).
- Hai Karate is referenced several times in the TV show Get a Life
- Hai Karate is referenced in an episode of Home Improvement
- Hai Karate is mentioned in the Freaks and Geeks episode "Girlfriends and Boyfriends".
- Hai Karate is mentioned in the "Uptown Friday Night" episode of Martin Lawrence's 90's comedy show Martin, when one of Martin's alter ego characters the "player" Jerome splashes some on exclaiming "No hottie can resist my body once I put on Hai Karate!"
- Hai Karate is mentioned in Season 3, Episode 1 of Sex and the City, "Where There is Smoke..."
- The lyric "He smells like Hai Karate" appears in the song "Nerdy Boys" by the band Candypants.
- The original radio spot from the 1960s is used on the SIRIUS XM station '60s on 6.
- A bottle of Hai Karate Cologne is seen on the desk in the opening credits of the movie Almost Famous.
- In the 1993 satire Loaded Weapon 1, Dr. Harold Leacher (a caricature of Hannibal Lecter played by F. Murray Abraham) comments that Sgt. Jack Colt, played by Emilio Estevez, smells of Hai Karate.
- In episode 249 of Cheers "The Magnificent Six", Sam Malone admits the cologne in his babe kit is a special blend of Old Spice, Hai Karate, and something that takes spots out.
- Hai Karate commercials are played throughout the 1999 British film Whatever Happened to Harold Smith?
- In episode 8 of "Freaks And Geeks" Bill asks "Should I wear Hai Karate or Old Spice".
- In the "She's..Back" episode of Wings Fay mentions that she catches a faint whiff of Hai Karate from one of her late husbands leisure suits.
- In the DC Universe The New 52 Suicide Squad issue #14, The Joker accuses Harley Quinn of getting "naughty with a guy (Deadshot) who wears Hai Karate for men"