Route 105 is a 29.36-mile-long (47.25 km) state highway in southeastern Massachusetts, running from Marion to Halifax in a generally north-south direction. Its southern terminus is at U.S. Route 6 (US 6) in Marion and its northern terminus is at Route 106 in Halifax. Along the way it intersects Interstate 195 (I-195) in Marion and Interstate 495 and US 44 in Middleborough.