Bennett Spring is an unincorporated community and census-designated place (CDP) in Dallas and Laclede counties, Missouri, United States. As of the 2020 census, Bennett Spring had a population of 138. It lies 12 miles (19 km) west of Lebanon on Missouri Route 64. The community is named after a spring that is reported variously as the third or fourth largest in the state, with an average daily flow of about one hundred million gallons, and which is the centerpiece of Bennett Spring State Park.