The Rams announced earlier this month that Simmons would transfer.
A 6-foot-9, 250-pound redshirt freshman from Miami, Fla., Simmons had appeared in only three of VCU's eight games this season and posted averages of 0.7 points and 0.7 rebounds.
He will have three years of eligibility with the Eagles starting after the Fall 2015 semester.
"We're excited about Antravious joining the program," FGCU head coach Joe Dooley said in a news release. "He's a quality, high-character person that we want. He'll be a great fit into our style of play."
Simmons was a three-star prospect in the class of 2013 who drew scholarship offers from Kansas State, Memphis, Miami and South Carolina, among other programs, according to the recruiting service Rivals.com.
Florida Gulf Coast has posted an 8-2 record so far this season.