Barry County is a county located in the southwest portion of the U.S. state of Missouri. As of the 2020 Census, the population was 34,534. Its county seat is Cassville. The county was organized in 1835 and named after William Taylor Barry, a U.S. Postmaster General from Kentucky. The town of Barry, also named after the postmaster-general, was located just north of Kansas City, not in Barry County.