1984 (MCMLXXXIV) was a leap year starting on Sunday of the Gregorian calendar.
- January 14: Andy Gibb performs at the Rivera Hotel in Las Vegas
- July 6: Andy Gibb plays at the Ginásio do Ibirapuera in São Paulo, Brazil
- October 24: The album Guilty is certified multiplatinum in the US
- November 7: The album Saturday Night Fever( is certified multiplatinum in the US
- November 25: Andy Gibb appears on an episode of the NBC sitcom Punky Brewster
- December 1: Barry's son Michael Gibb is born