In competition, Grand Slam may refer to:
- Grand slam (baseball), a home run with the bases loaded.
- Grand Slam (tennis)
- Grand Slam (real tennis)
- Grand Slam of golf, winning The Masters, U.S. Open, The Open Championship (British Open), and the PGA Championship in one year
- Grand Slam (Rugby Union)
- Grand Slam Champion of professional wrestling
- Grand Slam (PBA) of the Philippine Basketball Association
- In cyclo-cross, winning the World and National Championships, the Superprestige, the GvA Trophy, and holding the No. 1 spot on the UCI rakings in one year
- In NASCAR, the Daytona 500, Aaron's 499, Coca-Cola 600, and Southern 500.
- In contract bridge, bidding for and winning all the tricks in one hand
- In snooker, holding the Grand Prix, British Open, UK Championship, Irish Masters, Welsh Open, European Open, Players Championship and Embassy World Championship titles at the same time
- In ski jumping, winning the Four Hills Tournament
- In American professional sports, those cities which have at least one franchise in all four major professional sports leagues (Grand Slam Cities)
- In beauty pageantry, when a country wins more than one of the Big Four events in a single year
- In acting, winning major awards in the same category
Grand Slam may also refer to:
Голям шлем | Grand Slam | Grand Chelem | 그랜드 슬램 | Grand Slam | גראנד סלאם | Grand slam | グランドスラム | Grand slam | Wielki Szlem | Grand Slam | Турниры Большого шлема | Grand Slam | 大满贯