Grass River Provincial Park is a 2,279 km2 provincial park in Northwestern Manitoba, Canada. Designated in 1963, the park is approximately 75 km north of The Pas and is centered on the Grass River. The southern part of the park includes portions of the dolomitic Manitoba Lowlands portion of the Interior Plains, while the northern portion includes part of the granitic Canadian Shield. It it crossed east-west by Manitoba Highway 39 (PTH 39), with PTH 10 crossing the western edge of the park. The entire park shows evidence of glaciation. The park is considered to be a Class III protected area under the IUCN protected area management categories. During the 20th century a number of mines operated in the park, the last of which closed in 1993.