Wabaunsee County is a county located in the U.S. state of Kansas. Its county seat is Alma. As of the 2020 census, the county population was 6,877. The county was named for Chief Waubonsie of the Potawatomi Indians.

Waubonsie was a leader of the Potawatomi Native American people. His name has been spelled in a variety of ways, including Wabaunsee, Wah-bahn-se, Waubonsee, Waabaanizii in the contemporary Ojibwe language, and Wabanzi in the contemporary Potawatomi language.