The Harbin–Tongjiang Expressway (Chinese: 哈尔滨—同江高速公路), commonly referred to as the Hatong Expressway (Chinese: 哈同高速公路) is an expressway that connects the cities of Harbin, Heilongjiang, China, and Tongjiang, a county-level city in Jiamusi, Heilongjiang. It is completely in Heilongjiang Province. The section from Jixian County to Tongjiang is not built yet.
The expressway is a spur or auxiliary line of the G10 Suifenhe–Manzhouli Expressway. The Harbin–Tongjiang Expressway meets the Suifenhe–Manzhouli Expressway at Harbin.
The expressway passes through the cities of Harbin, Jiamusi, Shuangyashan, and ends at Tongjiang, which is a county-level city of Jiamusi.