Cat Creek (also Frantz or Frantzville) is an unincorporated community in eastern Petroleum County, Montana, United States. The Cat Creek community (also known as the Shay community) is located in Cat Creek Basin, in a "fertile valley land", 6 miles (9.7 km) long and 4 miles (6.4 km) wide, consisting of 16,000 acres. It lies along local roads east of the town of Winnett, the county seat of Petroleum County.