The Fort Foster State Historic Site is a historic area and park in Thonotosassa, Florida. It is best noted for being the location of the 1836 Fort Foster.

Fort Foster was built in 1836 for the Second Seminole War. It was used to safeguard the nearby bridge spanning the Hillsborough River and to maintain the communication from Tampa to Ocala. The site was used in 1838 and then in the late 1840s when the Seminoles threatened again. The current site features reconstructions of the original log fort.

The Fort Foster State Historic Site is a part of the Hillsborough State Park. It is home to the annual Fort Foster Rendezvous with reenactments. The site is accessible through the tours leaving from Hillsborough every hour on weekends.