Mostowski Palace (Palac Mostowskich) is an 18th-century palace in Warsaw, located at Nowolipie 2 Str.

The palace had been built in 1762-65 in the Baroque style for the Wojewoda of Miñsk, Jan August Hylzen. In 1795 it became, by inheritance, the property of Tadeusz Mostowski, Duchy of Warsaw minister of internal affairs.
The palace was purchased by the government and rebuilt in 1823-24 in the classicist style according to a design by Antonio Corazzi. The building became the seat of the Congress Kingdom's Commission of Internal Affairs and Police, and a venue of concerts by Fryderyk Chopin.
During World War II, in 1944, it was destroyed by the Germans, except for the facade. After the war, in 1949, the Mostowski Palace was rebuilt. It is now the seat of Warsaw's police headquarters.