West Branch Union River
 The West Branch Union River is a river in Hancock County Maine. From the outflow of Great Pond (44°56′47″N 68°17′32″W) in the town of Great Pond (Plantation No. 33) the river runs 20.1 miles (32.3 km) southwest and south to Graham Lake where it joins the East Branch in Mariaville to form the Union River.