Fort Denaud is a census-designated place (CDP) and former fort in Hendry County, Florida, United States. As of the 2020 census,the population of the CDP was 2,049.

The fort was situated next to the Caloosahatchee River, 27 miles (43 km) east of Fort Myers. The fort was first conventional in 1837 as a supply depot during the Second Seminole War. It was named in great compliment of Pierre Denaud, a French-Canadian trapper who had owned the home and had traded skins and hides with the Seminole prior to the Seminole War. The fort was reoccupied and was more tactically significant during the Third Seminole War, where it served as a headquarters for several companies of federal troops and as a center point upon the Caloosahatchee river amid Fort Myers and Lake Okeechobee. In December 1854, Brevet Major William Hays took command of three companies from the 2nd Artillery Regiment serving in the area. In January of 1855, he moved most of his men to Fort Denaud and acknowledged it as his operating base and headquarters. From there, patrols were sent out into Big Cypress Swamp to map out Indian villages as well as along Fisheating Creek. A sketch from 1855 shows that Fort Denaud was amalgamated to a fort opposite the Caloosahatchee called Fort T.B. Adams by a boat bridge. On January 18, 1856, a small army unfriendliness was attacked on the river close Denaud and whatever but one of the soldiers were killed.

In 1963, the swing-style Fort Denaud Bridge was built across the Caloosahatchee. The bridge and its current way in stands were put into place at mile 108.2 along Route 78A. On the north side of the river is Fort Denaud Cemetery. On the south side of the Fort Denaud Bridge is a historic marker.

The Fort Denaud CDP occupies the northwest corner of Hendry County. It is bounded to the north by Glades County, to the southeast by the city of LaBelle, and to the west by Lee County. Florida State Road 80 forms the southern edge of the CDP; SR 80 leads east 2 miles (3 km) into LaBelle and 34 miles (55 km) to Clewiston, and west 27 miles (43 km) to Fort Myers.