To determine the main morphological traits that influence the body weight of the Chinese soft-shelled turtle, Trionysx sinesis, carapace length, plastron length carapace width and body height of 100 day-old and 300 day-old turtles were measured. Results showed that carapace length, carapace width, body height and plastron length were significantly correlated with body weight(P＜0.01), the correlation index were 0.891, 0.651, 0.907 and 0.671 for 100 day-old T. sinesis and 0.724, 0.606, 0.625 and 0.424 for 300 old-day T. sinesis, respectively. Path coefficients and coefficient of determination analysis indicated that carapace length and plastron length significantly affected body weight for 100 old-day turtle, and the direct effect index was 0.541 and 0.469, respectively. The coefficient of determination of the two attributes on weight body for 100 old-day turtle was 0.909. Carapace length and body height significantly affected body weight for 300 old-day turtle, and the direct effect index was 0.711 and 0.402, respectively. The coefficient of determination of the two attributes on body weight for 100 old-day turtle was 0.785.