Highway 309 is a provincial highway in the Canadian province of Saskatchewan. It runs from Highway 9 near Ebenezer to Highway 637 in Rhein. It is about 18 kilometres (11 mi) long, and is concurrent with Highway 726 for its entire length.

Hwy 309 begins in the Rural Municipality of Orkney No. 244 at an intersection with Hwy 9 (Saskota Flyway) just immediately to the south of the village of Ebenezer, with the road continuing west as Hwy 726. Concurrent (overlapped) with Hwy 726, the pair head due east to cross a railway and enter the Rural Municipality of Wallace No. 243, travelling through rural farmland for several kilometres to enter the village of Rhein. The highway crosses over a former railway line before coming to an end on the north side of town at the junction with Hwy 637 (Church Street), with Hwy 726 continuing east. The entire length of Hwy 309 is a paved, two-lane highway.

From west to east: