In order to detect the correlation between quantitative characters for one new variety "Shenzhe No. 1" of Sinonovacula constricta at different months of age, more than 60 individuals of S. constricta at 4^th, 9^th and 11^th month age were randomly selected to measure the shell length (SL), shell height (SH), shell width (SW) and body weight (W). And the correlation and path analysis method were used to analyze the effect of phenotypic character on qualitative traits. Then results showed that the correlations among the qualitative characters reached extremely significant levels. The shell length showed the greatest correlation coefficients to the live weight of the 4-month age and 11-month age (0.911 and 0.631) respectively. However, the shell height showed the greatest correlation coefficients to the weights of the 9-month age (0.653). The result of the path coefficient analysis showed that the highest path coefficients were the shell length (0.562), shell width (0.433), and shell height (0.394) at 4^th, 9^th and 11^th month age, respectively. The results of the determinant coefficients were consistent with the results of the path analysis. The multiple regression equations were obtained to estimate live weight of S.constricta as 4^th, 9^th and 11^th month age weights (W):W₄=-0.756+0.039SL+0.112SW, R²=0.849; W₉=-10.622+0.095SL+0.404SH+0.644SW, R²=0.631; W₁₁=-23.772+0.207SL+0.805SH+0.587SW, R²=0.909. The study provides theoretical basis and good measures for the selection of the parents and aquaculture production forecast in the breeding of S. constricta.