Tjøme is an island in Færder Municipality in Vestfold county, Norway.

The 24.5-square-kilometre (9.5 sq mi) island lies immediately south of the large island of Nøtterøy, between the Ytre Oslofjord (to the east) and the Tønsbergfjorden (to the west).

The highest point on the island is the 78-metre (256 ft) tall hill Herkelås.

The bedrock forming the island consists of syenite, and the depressions on the island are covered by sand and clay.

The shoreline can be rocky, but there are some beaches as well which draw significant numbers of summer tourists.