Gansu (simplified Chinese: 甘肃; traditional Chinese: 甘肅; pinyin: Gānsù (info • help); Wade–Giles: Kan-su, Kansu, Kan-suh) is a province of the People's Republic of China. The capital is Lanzhou, in the southeast part of the province.
It has an area of 454,430 km². As of 2010 about 25,575,000 people were living here; in 2018, the population is 26,257,000.
Most people of Gansu are Han Chinese.
The province is mountainous in the south but flat in the north.