Kampinos Forest (Polish: Puszcza Kampinoska) is a large forest complex located in Masovian Voivodeship, west of Warsaw in Poland.

The forest began to form 14-11,000 years ago, at the very end of the Last Glacial Period.

In its present day form, most of the woodland is no longer old-growth forest but rather the remainders of a once-managed forest which is now left to grow on its own, with little human intervention.

Among the distinctive features of the area is a combination of sandy dunes and marshes, with dense pine and spruce forest.

The forest is a Natura 2000 EU Special Protection Area.