Osceola County is a county located in the central portion of the U.S. state of Florida. As of the 2020 census, the population was 388,656. Its county seat is Kissimmee. Osceola County is included in the Orlando–Kissimmee–Sanford, Fla. Metropolitan Statistical Area. Being 54.3% Hispanic, Osceola is one of three Hispanic-majority counties in Florida, owing to its large Puerto Rican American population. It also is the 12th-largest majority-Hispanic county in the nation.