This paper presents preliminary analysis on the namics and characters of individual fecundity of the.geaocypris daaidz (Bleaker)Guanting reservoir. 11Ta-terials were coiiected in 1952, 144 samples ware studied, the results are summarized as follows: 1.The individual absolute fundity (r) varied between 42177 and 2fi5949(egg) (average, 115769);the individual relative fecundity r/L varied between 156 and799 (eggs/mm) (averagr, 414) and W between 127 and 447 (eggs/g) (average, 387). 2. The variability is shown in diagrams of fecundity and body-length, body-weight and age groups in Figs 1-5.he relationship between the individual absolute fecundityand length (L) is indicated by the exponential equation The relationship between tha individual absolute fecundity (r) and body weight (civ) is expressed by the following equation : r=496W一32&30, 3. The fecundity coefficient (C=L"ylr/r) varied between 0.5 and i.74(mm. g/e)，mostly between 0. fi and 0. 9 (mm g/eggs).The individual absolute fecundity (r) was found t.o ire related to "L"W" and “L"W Iinearly, it also likely relaters between indiv idual fecundity (,r/L) and body-weight. 4. The individual fecundity (r, g/L) not increases with increase of length and weight, but also variers with the peculiarity of maturation coefficient, eggs diame- ter, age and the coefficient of condition (W/LS x. 104):among these niorphologi- cal indic)s, body weight is the,t distinct and followed by the length, maturation coefficient, egg diameter, coefficient of condition (T) and the age at the last.