Duboistown (DOO-boiz-toun), borough (1990 pop. 1,201), Lycoming co., N central Pa., residential suburb, 2 mi/3.2 km WSW of Williamsport, on West Branch of Susquehanna R. (bridged to Williamsports W end); 41°13'N 77°02'W. Susquehanna State Park to NW; part of Tiadaghton State Forest to S. Settled 1773, inc. 1878.