Heilongjiang (formerly romanised as Heilungkiang) is a province of the People's Republic of China. Located in the northeastern part of the country, Heilongjiang is bordered by Jilin to the south and Inner Mongolia to the west. It also shares a border with Russia to the north and east. The capital and the largest city of the province is Harbin. Among Chinese provincial-level administrative divisions, Heilongjiang is the sixth-largest by total area and the 15th-most populous.
The province takes its name from the Heilong River (Chinese name of the Amur), which marks the border between the People's Republic of China and Russia. Heilongjiang contains China's northernmost point (in Mohe County along the Amur) and easternmost point (at the junction of the Amur and Ussuri rivers).
Heilongjiang is China's largest agricultural base, as well as an important industrial area mainly based on oil, timber, coal and machinery manufacturing.