Pentwater is a village in Oceana County in the U.S. state of Michigan. The population was 890 at the 2020 census. The village is located within Pentwater Township. Pentwater is home to Mears State Park. The name Pentwater comes from Pent or Penned up waters. The entrance to the channel is notoriously shallow and for many years dictated the size of vessels that the village was able to accommodate.

Oceana County is a county located in the U.S. state of Michigan. As of the 2020 Census, the population was 26,659. The county seat is Hart. Long known as part of the large Ojibwe territory, the county was founded by European Americans in 1840 and organized in 1855.