Abstract: This study aimed to evaluate the effect of early forced supplementary feeding on weight gain and rearing benefit of different breeds of lamb in Lanzhou of Gansu Province. Ten healthy lambs for each breeds of Hu Sheep, small-tail Han Sheep, F1 hybrids of Dorper Sheep and Hu Sheep, and F1 hybrids of Dorper Sheep and small-tail Han Sheep were selected in this study, and the lambs in the same breed were included in the same group. From 7-day-old to weaning （60-day-old）, the lambs were subjected to early forced supplementary feeding by feeding with starter. The lambs were weighed at the date of birth and weaning, and the average daily gain of different groups were calculated and statistically compared; the diseases incidence was recorded and compared; the body measurement indicators were determined at the weaning day and were statistically compared; the rearing benefit of different groups were calculated and compared. The results showed compared to Hu Sheep and small-tail Han Sheep lambs, the Fl hybrids of Dower Sheep and small-tail Han Sheep as well as Fl hybrids of Dorper Sheep and Hu Sheep lambs had significantly higher average daily gain （P〈0.05）; the Hu Sheep and Fj hybrids of Dorper Sheep and small-tail Han Sheep lambs had higher diseases incidence than small-tail Han Sheep and F1 hybrids of Dorper Sheep and Hu Sheep lambs; the chest width of the 60-day-weaned F1 hybrids of Dorper Sheep and small-tail Han Sheep lambs was significantly higher than that of Hu Sheep and small-tail Han Sheep lambs （P〈0,05）, and was higher than that of F1 hybrids of Dorper Sheep and Hu Sheep lambs （P〉 0.05 ）; no significant differences in the other body measurement indicators were found （P〉0.05） between the four breeds of lambs; the rearing benefit of F1 hybrids of Dorper Sheep and small-tail Han Sheep, Fi hybrids of Dower Sheep and Hu Sheep and Hu Sheep lambs was 90.92 Yuan, 67.18 Yuan and 3.31 Yuan higher than that of small-tail Han Sheep lambs, respectively. The results obtained in this study suggest that early forced supplementary feeding by feeding starter effectively improves the production performance and rearing benefit, and this supplementary feeding technique is worthy to be promoted and applied in Lanzhou area.