Kampinos Forest () is a large forest complex located in Masovian Voivodeship, west of Warsaw in Poland.
It covers a part of the ancient valley of the Vistula basin, between the Vistula and the Bzura rivers. The forest began to form 14-11,000 years ago, at the very end of the Last Glacial Period.
Once a forest covering 670 km<sup>2</sup> of central Poland, it currently covers roughly 240 km<sup>2</sup>. 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.
Most of the Kampinos forest is currently protected within Kampinos National Park (Kampinoski Park Narodowy).
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.