Objective：To explore the influence of two different feedings，on the basis of parenteral nutrition，on the premature in－fants’ Leptin and Insulin-like growth factor-1（IGF-1）expression levels. Methods：On the first and second day，64 premature infants in ICU，on the basis of parenteral nutrition，were fed with 5 ml/（kg·d） milk each day，and were fed with 15 ml/（kg·d） milk on the third day. Then 31 of them were put into test group and 33 into control group by using random number table 72 hours later. The daily increment of feeding in test group was 30 ml/（kg·d） milk，and the increment was 20 ml/（kg·d） milk in the control，until the feedings of intestine reached 150 ml/（kg·d）. All the infants’ everyday weight and weekly height and head circumference were measured dur－ing the feeding；10 days later，the expression levels of Leptin and IGF-1 in blood serum were tested. Results：After one month，in－fants’ weight in the test group was significantly higher than that of control group （P<0.05）. The expression levels of Leptin and IGF-1 in blood serum in the test group were also higher than those of control group 10 days after the infants were born （P<0.05）. Conclu－sion：Parenteral nutrition mixed with an increasing amount of 30 ml/（kg·d） of enteral feeding can improve the expression levels of Leptin and IGF-1 in blood serum of preterm infants，and is conducive to the their growth.