Palm City is a census-designated place (CDP) in Martin County, Florida, United States. The population was 20,097 at the 2000 census. It is part of the Port St. Lucie Metropolitan Statistical Area. Palm City is located at 27Â°10â²16â³N 80Â°16â²43â³W / 27.17111Â°N 80.27861Â°W / 27.17111; -80.27861 (27.171127, -80.278657). According to the United States Census Bureau, the CDP has a total area of 16.6 square miles (42.9 kmÂ²), of which, 14.6 square miles (37.9 kmÂ²) of it is land and 2.0 square miles (5.1 kmÂ²) of it (11.76%) is water.