Uttarkashi District is a district of Garhwal division of the Uttarakhand state in northern India, and has its headquarters at Uttarkashi city. It has six Tehsils named after Badkot, Bhatwadi, Chinyali Sour, Dunda, Purola, Mori.

Uttarkashi District town lies high in the Himalaya range, and the district contains the source of both the Ganges and Yamuna rivers, which attract thousands of Hindu pilgrims. The town lies on the main route to Gangotri, has many Hindu temples, and is also considered an important Hindu pilgrimage centre. The district is bounded on the north by Himachal Pradesh state, on the northeast by Tibet, on the east by Chamoli District, on the southeast by Rudraprayag District, on the south by Tehri Garhwal District, and on the west by Dehradun District.

According to the 2011 census Uttarkashi district has a population of 329,686, roughly equal to the nation of Belize. This gives it a ranking of 567th in India (out of a total of 640). The district has a population density of 41 inhabitants per square kilometre (110/sq mi) . Its population growth rate over the decade 2001-2011 was 11.75%. Uttarkashi has a sex ratio of 959 females for every 1000 males, and a literacy rate of 75.98%.