Kozarnika (Bulgarian: Козарника) is a cave in the western Balkan Mountains of Bulgaria.

It is located near the village of Lipnitsa, Botevgrad municipality, 600 m from Preslavica neighbourhood.

Its total length is 89 m.[2] The cave has no waterways, it is easily passable and contains with a single winding gallery with one branch that stems from the main gallery.

The first 15 m of the gallery are high and wide but then it gets narrower and lower.

The fauna includes invertebrate trogophiles and trogloxene.