Petersville is a census-designated place (CDP) in Matanuska-Susitna Borough, Alaska, United States.

The small community of Petersville sits along Petersville Road on the east side of Peters Creek, 29 miles (47 km) northwest of Alaska Route 3 (the Parks Highway) at Trapper Creek, and 145 miles (233 km) north of Anchorage.

Petersville is categorized as being within the 3a USDA hardiness zone, meaning temperatures can get as low as −40 to −35 °F (−40 to −37 °C).

The racial makeup of the CDP was 88.89% White, 7.41% Native American and 3.70% Pacific Islander.

There were no families and none of the population living below the poverty line, including no under eighteens and none of those over 64.