The 1989–90 season was FC Dinamo București's 41st season in Divizia A. In this season, Dinamo made the double, stopping Steaua's supremacy in Romania. In Europe, Dinamo reached the semifinals of the Cup Winners' Cup, where it is defeated by Anderlecht. It was a special season because of the Romanian Revolution of 1989. Dinamo dominated the first half of the season, winning the derby with Steaua, 3–0, on its ground. It was the first defeat for Steaua in the Romanian championship after 104 consecutive games. In the winter break, after the Revolution, Dinamo suffered administrative changes, for a few days having a different name – Unirea Tricolor.
In the final of the season, because of the Romanian national team's qualification at the 1990 World Cup in Italy, FRF decided that the teams shall not use the chooseable players. However, in the game between Dinamo and Farul, Răducioiu and Lupu, respectively Marian Popa had played, managers and coaches of both clubs (Vasile Ianul and Lucescu for Dinamo) were suspended for three months, and the match, won by Dinamo 2-1 was replayed. To stay on the bench next stage Lucescu registered as a player, and even took the field, becoming at 45 years old, the oldest player in league history.
In the summer break, Dinamo brought Daniel Timofte from Jiul Petroșani and Anton Doboș from U.Cluj. Left the team Lică Movilă to Flacăra Moreni, Bogdan Bucur to Inter Sibiu, Rodion Cămătaru to Racing Charleroi and Dumitru Moraru to Vålerenga. Other two players, Gheorghe Viscreanu and Marcel Sabou, went to Spain. In the winter break, came to Dinamo Alexandru Nicolae from Victoria, Constantin Lazăr from Chimia Râmnicu Vâlcea and Mihai Stoica from FC Argeş.
