The Belgian Socialist Party (French: Parti Socialiste belge, pronounced [paʁti sɔsjalist bɛlʒ], PSB; Dutch: Belgische Socialistische Partij, pronounced [ˈbɛlɣisə ˌsoːɕaːˈlɪstisə pɑrˈtɛi], BSP) was a social-democratic political party which existed in Belgium from 1945 to 1978.

During its time in office, a number of progressive social reforms were introduced.

It ceased to function during the Second World War, while Belgium was under Nazi occupation.

Like most Belgian political organisations, the party supported greater integration with the European Economic Community, albeit in a socialist context.

Media related to Parti Socialiste (Belgium) at Wikimedia Commons