Objective:To study the effects of maternal malnutrition on the development and function of fetal pancreas. Methods:The newborn rat model with intrauterine growth retardation was established by maternal nutrition restriction(50% calorie restriction of the normal) during the 11th to 21st days of pregnancy. The growth and development status of the newborns,glucose tolerance test and immunohistochemistry analysis were investigated to evaluate the development and function of fetal pancreas. Results:Body,pancreas weight and the ratio of pancreas to body weight of newborns in IUGR group were much lower than those in normal group(P < 0.001). The fasting glucose and insulin levels of IUGR newborns were both lower than those of normal ones,whereas glucose levels at 120 min and 180 min after glucose challenge were significantly higher in IUGR group[(18.95 ± 2.63)mmol/L vs(16.92 ± 1.30)mmol/L;(18.29 ± 2.58)mmol/L vs (15.87 ± 2.08)mmol/L,P < 0.05]. In addition,areas of insulin-expression positive cells[(M=1 530.98 μm2,QU-L=2 961.98 μm2)vs(M=3 146.24 μm2,QU-L=4 633.73 μm2)] and positive rate of cells staining with insulin[(M=2.03%,QU-L=2.67%)vs(M=5.44%,QU-L=4.34%)] were also less than normal newborns(P < 0.01). Conclusion:Maternal malnutrition would lead to impaired pancreatic development and decreased islet area in newborn rats,as well as dysfunction of glucose regulatory capacity.