Abstract: Objective： To explore the correlation between hypoalbuminemia and immune level and iatrogenic infection in children with developmental dysplasia. Methods： A total of 100 cases of developmental dysplasia children with hypoalbuminemia treated in our hospital were selected as the hypoalbuminemia group (n=100) according to their clinical symptoms.While 100 healthy children with similar physical function had medical check-up in our hospital were chosen as the control group (n=100).Their physical condition， plasma albumin level， kinetic parameters plasma albumin metabolism， immunoglobulin expression and the incidence of iatrogenic infection were collected and compared between the two groups.Results：Compared with the control group， the plasma albumin level of the hypoalbuminemia group decreased， while the distribution rate (K12) and apparent distribution volume (Vd) levels increased， and the half-life (t1/2) level decreased， and the differences were statistically significant(P＜0.05).The level of immunoglobulin expression in the hypoalbuminemia group was lower than that of the control group， and the immune level of the patients decreased as well， and the differences were statistically significant (P＜0.05).The incidence of iatrogenic infection in the hypoalbuminemia group was higher than that in the control group， and the difference was statistically significant (P＜0.05).Correlation analysis showed that the serum albumin concentration was positively correlated with the immune level of patients (P＜0.05)， and negatively correlated with the incidence of iatrogenic infection (P＜0.05). Conclusion： The deficiency of immune system and its consequent iatrogenic infection are the key factors for hypoalbuminemia in developmental dysplasia children.Therefore， immune system should be improved and incidence of infections be reduced， which might prevent the children from hypoalbuminemia.