Abstract: To improve the efficiency of rice paddy and investigate the effects of stocking density on the growth of juvenile Cyprinus carpio rubrofuscus,the growth traits of the carps stocked in different densities were measured and analyzed.The three-week-old juveniles with initial average body weight of 0.35 g were stocked and reared for eleven weeks in indoor aquarium with different stocking densities of 43.48,86.96,173.91,and 347.83 individuals/m²,which were marked as M1,M2,M3 and M4,respectively.The results showed that stocking density had no significant effect on the survival rate.But,the body weight,length,daily weight gain(DWG),net yield(NY),condition factor(CF),coefficient of variation(CV)and specific growth rate(SGR)were decreased with the increasing of stocking density.The body weight,length,DWG,NY and SGR of M1 group were the highest.Furthermore,CV of M1 group was lower than that of M2 group.The result indicated that the optimal stocking density of juvenile Cyprinus carpio rubrofuscus in this growth period was M1(43.48 individuals/m²).