Abstract: During 1987-1991, an investigation on human cestode infections covering 53 061 inha bitants in 103 pilot sites from 28 counties in Yunnan Province was made by cluster and randomized sampling. The infection rates shown by fecal examination were as follows: Taenia sp. 0.9%, Hymenolepis diminuta 0.02%, H. nana 0.01%. Cestodes were found to be widely distributed in Yunnan, showing infection rate up to 2.2% in the northern part, but only 0.05% in the western part. Cestode infections were mainly concentrated in 5 counties: Lanpin, Dali, Jinhong, Yongde and Yinjiang, with infection rate ranged from 0.7% to 17.4%. The highest infection rate (47.4%) was viewed in Sangje township of Lanpin, which was successively followed by 10.7% in Zhoucheng township of Dali, and 6.3% in Manting township of Jinghong. The youngest victim was a 2 year old child while the oldest was a 80 year old person. The infection rates were demonstrated to vary considerably with sex, age, nationality and occupation. Hymenolepis was in scattered distribution; the most vulnerable group was children. Hymenolepis nana infection in 7 cases was the first record in Yunnan.