Sanacja was a Nationalist coalition party of the Second Polish Republic in the interwar years. It was created following the aftermath of the First World War by Jozef Pilsudski and Edward Rydz-Smigly.

Named after the Latin word for sanitation (sanatio), the party was formed primarily by former military officers disgusted with the corrupt nature of Polish politics. It represented a coalition of members from the right, the left, and centrists. Its main focus was to eliminate corruption within Poland and to minimize inflation.

The first Sanacja government was formed during the May 1926 constitutional reforms of the Second Polish Republic, and was headed by Naczelnik Jozef Pilsudski until his death in 1935. Following Pilsudski's death the party splintered into two factions between President Moscicki and Rydz-Smigly.