Treasure Island Causeway is a series of three bridges (the outer ones fixed, the middle one a bascule drawbridge) crossing Boca Ciega Bay between Treasure Island and St. Petersburg in Pinellas County, Florida.

Treasure Island's ownership of the causeway in St. Petersburg was part of a land agreement entered into when these two cities were born: St. Petersburg's founding fathers purchased the Municipal Beach on the shores of the neighboring Gulf of Mexico community, Treasure Island, outside its own city limits to ensure that residents would have direct access to the Gulf of Mexico for generations to come.

The western terminus is an intersection with Gulf of Mexico Boulevard (SR 699) in Treasure Island.

It quickly became a popular route to the Pinellas County barrier islands for beach getaways.

Construction was completed and the new Treasure Island Causeway was dedicated in ceremonies held on August 25, 2007.