Kissimmee, FL has a population of 66,840 and is the 554th largest city in the United States. The population density is 3,210 per sq mi which is 993% higher than the Florida average and 3443% higher than the national average. The median age in Kissimmee is 34 which is approximately 18% lower than the Florida average of 42. In Kissimmee, 46% of the population over 15 years of age are married, 38% speak English and 55% speak Spanish. 20% of Kissimmee residents were born in Florida, 32% were born out of state, 23% were born outside of the United States and 25% were foreign born.