The results of population dynamic, diurnal vertical migration and regression equation for the body weight and weight length of Leptodora kindti are reported. The maximum population density for Leptodora kindti was 1.775 ind./L in 1984, and 0.332 ind./L in 1985 at Station I, 1.214 ind./L and 1.547 ind./L at Station II, respectively. Changes in the relative numbers of animals at three specific depths (surface, 1.00 and 2.00 meter) occur with time. Surface changes arc of much greater magnitude, although highly significant difference exists at all three sampling depths. Preliminary investigation shows that the general pattern of diurnal migration is to be one in which more individuals were found at surface within one hour before and after sunrise and sunset, while less numbers were observed at surface during daytime. By weighted, the wet and dry weights were determined, and their relationships to the body length arc expressed by various regression equations.