Parliamentary elections were held in the Socialist Republic of Croatia between 22 and 23 April 1990; the second round of voting occurred on 6–7 May. These were the first free, multi-party elections held in Croatia since 1938, and the first such elections for the Croatian Parliament since 1913. Voters elected candidates for 356 seats in the tri-cameral parliament; the turnout in the first round ranged between 76.56% and 84.54% for various parliamentary chambers. In the second round, the turnout was 74.82%. The Croatian Democratic Union (HDZ) won 205 seats, ousted the League of Communists of Croatia – Party of Democratic Reform (SKH-SDP) from power and ended 45 years of communist rule in Croatia. The new parliament convened for the first time on 30 May, elected Franjo Tuđman as President of the Croatian Presidency and soon after renamed the office to President of Croatia.

The Constitution of the Republic of Croatia is promulgated by the Croatian Parliament.