"Don't Worry, Be Happy" is the title and principal lyric of a song by musician Bobby McFerrin. Released in September 1988, it became the first a cappella song to reach number one on the Billboard Hot 100 chart, a position it held for two weeks. On the UK Singles Chart, the song reached number 2 during its fifth week on the chart. At the 1989 Grammy Awards, "Don't Worry Be Happy" won the awards for Song of the Year, Record of the Year, and Best Male Pop Vocal Performance. The song's title is taken from a famous quote by Meher Baba. The original music video stars Robin Williams and Bill Irwin. The "instruments" in the a cappellasong are entirely overdubbed voice parts and other sounds made by McFerrin, using no instruments at all. The music video for the song is considerably shorter than the album version.

It is ranked #31 on VH1's 100 Greatest One Hit Wonders of the 80s.

The Indian mystic and sage Meher Baba (1894–1969) often used the expression "Don't worry, be happy" when cabling his followers in the West. However, Meher Baba communicated variations of the sentiment; fuller versions of the quote—such as, " Do your best. Then, don’t worry; be happy in My love. I will help you" -- also incorporate responsibility ("do your best...") alongside the detachment ("don't worry..."), as well as the master/disciple spiritual relationship ("I will help you"). In the 1960s, the truncated version of this expression by Baba was printed up on inspiration cards and posters of the era. In 1988, McFerrin noticed a similar poster in the apartment of the jazz band Tuck & Patti in San Francisco. Inspired by the expression's charm and simplicity, McFerrin wrote the now famous song, which was included in the soundtrack of the movie Cocktail, and became a hit single the next year. In an interview by Bruce Fessier for USA Weekend Magazinein 1988 McFerrin said, "Whenever you see a poster of Meher Baba, it usually says 'Don't worry, be happy,' which is a pretty neat philosophy in four words, I think."

Versions of "Don't Worry, Be Happy" have been recorded by several artists. The Katsimiha Brothers made a Greek cover of the song with original lyrics, and Montenegrin musician Rambo Amadeus made a parody entitled "Don't Happy, Be Worry," as a critique to the optimism of the music scene in the former Yugoslavia in the face of war and economic depression. The lyrics of "Fight the Power" by hip-hop artists Public Enemy also refer to "Don't Worry, Be Happy". This song is also added into the Big Mouth Billy Bass. Hermes House Band covered the song on their "Rhythm of the Nineties" album in 2009. Reggae artist Cas Haley covered the song as a hidden bonus track on his "Favorites" album (together with former Jah Roots lead singer, Josh Heinrichs).

The song, and its title are commonly repeated in US culture. Comedian George Carlin wrote in Napalm and Silly Puttythat many Americans would embrace the philosophy of denial in the song. The song was used in George H. W. Bush's 1988 U.S. presidential election campaign until McFerrin, who was a Democrat, objected and the campaign desisted. The song is frequently used in film and television soundtracks to accompany light-hearted scenes, such as in Flushed Away(2006), WALL-E(2008), The Fresh Prince of Bel-Air, The Simpsons, Futurama, Nip/Tuckand That 70s Show. It was also featured in the soundtrack to 1988 film Cocktail. It has also been used in an ironic context for shocking or traumatic scenes, such as in Dawn of the Dead(2004) and Jarhead(2005). The song has been used in various forms in TV advertising for brands including Alamo Rent A Car, Walkers and Huggies.

Originally released in conjunction with the film Cocktailin 1988, the song originally peaked at #88 on the Billboard Hot 100. The song was re-released the same year and peaked at #1 on September 24, 1988. The song also peaked at #11 on the Billboard Hot R&B/Hip-Hop Tracks chart and #7 on the Billboard Hot Adult Contemporary Tracks chart. The song was also a hit in the United Kingdom and peaked at #2 on the UK Singles Chart.

"Nel blu dipinto di blu (Volare)" · "Mack the Knife" · "Theme from A Summer Place" · "Moon River" · "I Left My Heart in San Francisco" · "Days of Wine and Roses" · "The Girl from Ipanema" · "A Taste of Honey" · "Strangers in the Night" · "Up, Up and Away" · "Mrs. Robinson"

"Aquarius/Let the Sunshine In" · "Bridge over Troubled Water" · "It's Too Late" · "The First Time Ever I Saw Your Face" · "Killing Me Softly with His Song" · "I Honestly Love You" · "Love Will Keep Us Together" · "This Masquerade" · "Hotel California" · "Just the Way You Are"

"What a Fool Believes" · "Sailing" · "Bette Davis Eyes" · "Rosanna" · "Beat It" · "What's Love Got to Do with It" · "We Are the World" · "Higher Love" · "Graceland" · " Don't Worry, Be Happy "

"Wind Beneath My Wings" · "Another Day in Paradise" · "Unforgettable" · "Tears in Heaven" · "I Will Always Love You" · "All I Wanna Do" · "Kiss from a Rose" · "Change the World" · "Sunny Came Home" · "My Heart Will Go On"

"Smooth" · "Beautiful Day" · "Walk On" · "Don't Know Why" · "Clocks" · "Here We Go Again" · "Boulevard of Broken Dreams" · "Not Ready to Make Nice" · "Rehab" · "Please Read the Letter"

"Use Somebody"