The 1978 FIFA World Cup, the 11th staging of the FIFA World Cup, quadrennial international football world championship tournament, was held in Argentina between 1 and 25 June.

The 1978 World Cup was won by Argentina who beat the Netherlands 3–1 at River Plate's home stadium Estadio Monumental in the Argentine capital of Buenos Aires after extra time in the final. This win was the first World Cup title for Argentina, who became the fifth team (after Uruguay, Italy, England and West Germany), to be both hosts and world champions. Argentina, the Netherlands and Brazil were the gold, silver and bronze medalists respectively. Iran and Tunisia made their first appearances in the finals. This was also the last World Cup tournament to use the original inclusion of 16 teams, only 15 teams (plus the host, who automatically qualified) had been allowed to qualify since the first World Cup in 1930 (the reigning title holders also received automatic qualification from 1934 through 2002); for the next World Cup in Spain, FIFA expanded that tournament to 24 teams.