The League of Communists of Slovenia (Slovene: Zveza komunistov Slovenije, ZKS; Serbo-Croatian: Savez komunista Slovenije) was the Slovenian branch of the League of Communists of Yugoslavia, the sole legal party of Yugoslavia from 1945 to 1990. It was established in April 1937 as the Communist Party of Slovenia and was the first autonomous sub-national branch of the federal party. Its initial autonomy was further amplified with the Yugoslav constitution of 1974, which devolved greater power to the various republic level branches.

In 1989, Slovenia passed amendments to its constitution that asserted its sovereignty over the federation, its right to secede and set foundations to a multi-party system. These amendments were bitterly opposed by the leadership of Serbia under Slobodan Milošević. On 23 January 1990, the Slovene delegation, headed by Milan Kučan, left the Party Congress of the League of Communists of Yugoslavia, leading to the collapse of the all-Yugoslav party.

On 4 February 1990, the League of Communists of Slovenia changed its name to the League of Communists of Slovenia – Party of Democratic Renewal (Zveza komunistov Slovenije – Stranka demokratične prenove, ZKS-SDP); shortly afterwards, it began negotiations with the Democratic Opposition of Slovenia for the establishment of a multi-party system. In April 1990, the reformed Communists lost the elections to the DEMOS coalition.

Other influential leaders