Waynesville is a village in Wayne Township, Warren County, Ohio, United States. The population was 2,669 at the 2020 census. It is named for General "Mad" Anthony Wayne. The village, located at the crossroads of U.S. Route 42 and State Route 73, is known for its antique stores and its annual sauerkraut festival. Caesar Creek State Park is located 5 miles (8.0 km) east of the village.

Wayne Township is one of the eleven townships of Warren County, Ohio, United States. It is located in the northeast part of the county and includes the village of Waynesville, Ohio. The population was 8,658 at the 2020 census. Caesar Creek State Park is located in the township.