Abstract: Objective To study the mosquito community of human rooms in the lower valley of Lancang Jiang river, Yunnan province. Methods CDC light traps were used to collect mosquitoes in human rooms all night and species data were analyzed by entomological community methods. Results 3357 mosquitoes were collected and identified as 17 species of 8 subgenera, 6 genera, 2 subfamilies. The dominant species were Culex tritaeniorhynchus(28.09%), Anopheles minimus(25.92%) and An.sinensis(23.03%) respectively and the dominance(D) exceeded 40. Simpson's index of dominant centralization(C), Shannon-Wiener's diversity index(H′) and evenness(E) were 0.21, 1.82 and 0.55 respectively. Compared the Chi-square (P>P_0.05) with the Regressive analysis (r>0.325), the results revealed that the combining level were fine between An.minimus and Cx.fuscocephalus, An.maculatus and Cx.pseudovishnui, Cx.whitmorei and Cx.bitaeniorhynchus. Conclusion Mosquito species are abundant in human rooms of the lower valley of Lancang Jiang river and the community structure and component are relatively complicated, the distributions of dominant species are basically even and stable.