The experiment was conducted to study the effects of medium and high aquaculture density on the growth, survival, digestion and non-specific immunity of the current year Coilia nasus. A 96 days aquaculture experiment was conducted in the same batch of artificially bred Coilia nasus using pond culture methods. The results showed that the growth rate of body length and body mass in medium density pond (62#, 6 ind./m²) was significantly higher than that in high density pond (56#, 11 ind./m²), in which the relative growth rate of body length was 3.4 times than that in 56# pond, the relative body mass growth rate was 6.5 times than that in 56# pond. The faness and survival rate were also greater than those of 56# pond (0.290 g/cm³ and 83.5%, 0.278 g/cm³ and 79.7%, respectively). During the aquaculture period, the amylase (AMS) activity in 62# pond was significantly higher than that in 56# pond and showed a trend of increased first and then decreased with the aquaculture time, while the trypsin (TPS) activity showed a change of decreased first and then increased. Except that there was no significant difference between 62# pond and 56# pond in middle stages of aquaculture, the other time was significantly greater than 56# pond. The pepsin (PPS) activity in 62# pond was significantly higher than that in 56# pond and then gradually decreased to significantly lower than in 56# pond, while PPS activity in 56# pond did not change significantly change with time. The lipase (LPS) activity in 62# pond increased gradually with culture time, and was not significant different from that in 56# pond in middle stage, and was significantly smaller than that in 56# pond at other times. There was no significant difference in the activity of superoxide dismutase(SOD) between two ponds, but it decreased gradually with the time of aquaculture. The activity of catalase (CAT) and glutathione peroxidase (GSH-Px) in 62# pond was significantly higher than those in 56# pond. The CAT activity increased significantly with the aquaculture time, and GSH-Px activity did not change significantly. The CAT activity in 56# pond showed a trend of increased first and then decreased, while GSH-Px activity gradually decreased with aquaculture time. Therefore, under the experimental conditions, high-density aquaculture has a certain negative impact on the growth rate, digestive ability and immune system of juvenile Coilia nasus, while the growth, digestion and immunity of Coilia nasus cultured at medium density are superior to those at high density, which is more suitable for the cultivation and large-scale aquaculture of Coilia nasus.