The Hunter 31 is a recreational keelboat built by Hunter Marine in the United States between 1983 and 1987.
In 2006 the company introduced a new boat under the same Hunter 31 name, but it is commonly referred to as the Hunter 31-2 or Hunter 30/31 to differentiate it from this design. It is sometimes confused with the 2015 Marlow-Hunter 31.
The fiberglass hull has a reverse transom. The full keel boat has a PHRF racing average handicap of 168 with a high of 174 and low of 162. The shoal keel version has a PHRF racing average handicap of 171 with a high of 180 and low of 162. Both models have hull speeds of .