Abstract: Based on some 1100 specimens collected since 1958, the correlationship between fish diversity and 7 environmental factors of 6 lakes of central Yunnan are statistically investigated by employing multivariate andmultinomial stepwise regression analysis. Investigation reveals that the first and second determinantscontrolling the species richness, numbers of genera and endemic species of lacustrine fishese are respectivelythe area of the lakes and length of shoreline. The length of shoreline is negatively correlated to the lacustrinefish diversity and the area positively to the lacustrine fish diversity. Length of shoreline and area are the mainmorphometric characters indicating the development stage of a lake. Therefore lacustrine fish diversity isactually controlled by the development of the lake. A lake in the prime period usually has a relatively largerarea, shorter shoreline and a more rich fish diversity than a lake in the late period does.