Son La city is located in the center of Son La province. The average altitude above sea level is from 700 - 800 m. Geographic coordinates are from 21°15' to 20°31' North latitude and from 103°45' to 104°00' East longitude. The North and West border Thuan Chau district; The northeast borders Muong La district; The southeast and south border Mai Son district. Son La city has a national highway passing through (Hanoi - Son La - Dien Bien), from Hanoi to Son La city center is 320 km, the section through the inner city of Son La city is 15.6 km long. The city is the intersection of three important national highways: National Highway 6, National Highway 4G, National Highway 279D, creating convenient connections with important economic development centers: Hanoi, Phu Tho, Hoa Binh, is the convergence point of economic, urban, and road traffic infrastructure of the Northwest subregion.

Son La city has 12 administrative units including 7 wards and 5 communes: Chieng Le Ward, To Hieu Ward, Quyet Thang Ward, Quyet Tam Ward, Chieng An Ward, Chieng Coi Ward, Chieng Sinh Ward, Chieng Co Commune, Chieng Co Commune, Chieng Den, Chieng Xom Commune, Chieng Ngan Commune, Hua La Commune. Population of 103,820 people with many ethnic groups living. Among them, the most numerous are the Thai, Kinh, Muong, and Mong ethnic groups, the rest are other ethnic groups.

Son La city has a total natural area of 32,351 hectares. The average annual temperature is 21°C; hot and rainy from April to September, cold and dry from October to March of the following year. The climate compared to other districts is relatively mild. In the city, there is the 25km long Nam La stream, in addition to many small streams scattered in the communes of Hua La, Chieng Co, and Chieng Den.

Son La city is located in the key economic triangle of the province (Mai Son - Son La city - Muong La) and is the political-economic, cultural-social and security-defense center of the province. has an important strategic role and position in the economy and defense of the province and the Northwest region.