A large portion of the population are of Lahu ethnicity, and Lahu language is one of the official languages in the county. The Akha language, whose speakers are officially classified as Hani people, is also spoken in Lancang County. Ethnic Hani townships include Fazhan 发展河哈尼族乡 and Jiujing 酒井哈尼族乡 townships. Menglang 勐朗镇 and Huimin 惠民镇 were formerly ethnic Hani townships, but are now towns. The Bisu language is spoken in the townships of Zhutang 竹塘乡, Laba 拉巴乡, Donglang 东朗乡, and Fubang 富邦乡. Yi people also live in Lancang County, and are found in Qianliu Ethnic Yi Township 谦六彝族乡. The Aciga 阿茨戛 people of Lancang County numbered about 50 individuals as of 1960, and are located in Yakou Township 雅口乡 and Nanxian Township 南现乡. Their original language has become extinct, and the Aciga now speak Chinese and Yi. The Aciga are currently classified by the Chinese government as ethnic Yi. Two dialects of the Wa language are spoken in Lancang County.
Aishi 艾师 subdialect of Baraoke in Donghe 东河, Wendong 文东, Shangyun 上允, Xuelin 雪林
Xiyun 细允 subdialect of Awa in Xiyun 细允 village of Donghui 东回
Wa townships include Xuelin 雪林佤族乡, Ankang 安康佤族乡, and Wendong 文东佤族乡 ethnic Wa townships. Bulang people are located in:
Lancang County is located in southwestern Yunnan below the Tropic of Cancer, spanning latitude 22°01'−23°16' N and longitude 99°29'−100°35' E and an area of, making it the second-largest county in the province in terms of area. It has an international border with Burma's Shan State totaling in length. It is heavily mountainous and situated among the Hengduan Mountains, with the elevation ranging from at Mount Malihei in Xincheng Township to in Yakou Township. Lancang County contains elements of both a tropical wet and dry climate and a humid subtropical climate, and is generally humid. Summer is long and there is virtually no "winter" as such; instead, there is a dry season and wet season. A drier heat prevails from February thru early May before the onset of the monsoon from the Indian Ocean. The monthly 24-hour average temperature ranges from in January to in June, while the annual mean is. Rainfall totals about annually, with nearly 70% of it occurring from June to September, when relative humidity averages above 85%. With monthly percent possible sunshine ranging from 24% in July to 70% in February, the county receives 2,116 hours of bright sunshine annually.
