Heihe–Tengchong Line

The Heihe–Tengchong Line (simplified Chinese: 黑河–腾冲线; traditional Chinese: 黑河–騰衝線; pinyin: Hēihé–Téngchōng xiàn), also called the Aihui-Tengchong Line (and internationally as the Hu line), is an imaginary line that divides the area of China into two parts with contrasting population densities. It stretches from the city of Heihe in the northeast to Tengchong in the south, diagonally across China. The eastern portion, area shown in red in the map, is further subdivided into north and south halves.

As of 2015, 43% of the Chinese territory is east of the line and has 94% of the country's population, and 57% of the Chinese territory is west of the line and has only 6% of the country's population.