Green River Reservoir State Park is a 5,500 acres (2,227 hectares) state park in Hyde Park, Vermont, on the shore of 653-acre Green River Reservoir (264 ha).

Activities includes camping, swimming, boating, fishing, picnicking (at designated da-use-sites, access by boat only), wildlife watching.

Day use is allowed in limited capacity. Only boats powered by electric motors up to 5 mph and human-powered watercraft are allowed.

The park features 28 remote campsites around the reservoir, which can be reached only by boat.

The park is undeveloped, with only low-impact recreational use allowed on and around the reservoir. Parking is limited.