Abstract: To investigate the effect of enzymatic hydrolyzed bone powder (EBP) on calcium supplement for low calcium rats. 6-week low calcium diet was used to establish a low calcium model. EBP (200, 400, 800 mg/kg) was orally administered to low calcium rats respectively for 4 weeks. The femur of rats was analyzed by HE staining.The mechanical index, dry weight, ash weight,and bone mineral density of the femur were measured. Femur calcium content, femur phosphorus content and the apparent absorption rate of calcium were determined. Results show that the bone trabecula is significantly decreased and the bone marrow cavity is remarkably enlarged in low calcium rats. After administration of EBP, the number of bone trabecula has increased and the area of bone marrow cavity has decreased. The bone mineral density of rats in high dose EBP can enhance by 14.1%. Besides, the content of calcium and phosphorus in the femur and the apparent absorption rate of calcium can increase significantly (p<0.05). These findings suggest that EBP can promote calcium absorption, increase bone mineral density and bone calcium content in low calcium rats, being a potential calcium supplement.