Route 690 is a 45.6-kilometre (28.3 mi) long mostly north–south secondary highway in the southwestern portion of New Brunswick, Canada.

The route starts at Route 10 between Minto and Newcastle Bridge, where it travels southeast through a mostly forested area to Newcastle Creek on the east bank of Grand Lake.

It then travels to Douglas Harbour before turning northeast to Clarks Corners.

The road again turns southwest, and it passes Hunters Ferry Cove, Hunters Island and Maquapit Lake before intersecting with Route 670 in Lakeville Corner.

From here, the road travels southwest through Fulton Island, past Harrison Island, to end at McGowans Corner at Route 105 on the Saint John River.