Ontario Highway 556

Route information
Length	110 km (68 mi)
Major junctions
Major intersections

Highway 556 is a secondary highway in the province of Ontario, Canada. Its western terminus is at Highway 17 in the hamlet of Heyden, just north of Sault Ste. Marie. Its eastern terminus is at Highway 129.

It is Template:Km to mi in length, of which only Template:Km to mi are paved. This paved section runs from its western terminus to its intersection with Highway 532 near Searchmont and is therefore informally known as the Searchmont Highway. From this point, the highway surface is rough gravel for its remaining length. Ranger Lake is the only community on this portion of Highway 556. Despite its relatively poor surface, it is considered an alternate link between Chapleau and Sault Ste. Marie.