Jastarnia [jasˈtarɲa] (Kashubian: Jastarniô, German: Heisternest) is a resort town in Puck County, Pomeranian Voivodship, northern Poland.

It is located on the Hel Peninsula on the Baltic Sea.

It is a popular Polish seaside resort and small fishing port.

The place was mentioned as "Osternese" in 1582, which is derived from North Germanic.

This Puck County location article is a stub.