Abstract: Objective:To study the content of calcium in mulberry leaf powder by using mulberry leaves produced in Dazhu County,Sichuan Province,and to explore the bioavailability.Methods:The total calcium content and amino acid categories and content of mulberry leaf powder were determined,and the calcium content of different forms was measured.The bioavailability of mulberry leaf powder was studied by simulating gastric and intestinal digestion. Results:The calcium content in the samples reached 1614.85 mg/100 g,the water-soluble calcium,pectin calcium and calcium carbonate were close to 60% of the total calcium content.The mulberry leaf powder could slowly release calcium under the action of gastric acid Ion,which can reduce the stimulation of the stomach compared to calcium carbonate and calcium gluconate. And the calcium permeability in the intestine was significantly higher than that of calcium carbonate and calcium gluconate (p<0.05). Mulberry leaf powder contains a wide variety of amino acids with appropriate proportion,EAA/TAA=40.79%,EAA/NEAA=68.88%,which was close to the FAO/WHO standard model. Conclusion:Mulberry leaf powder contains a variety of calcium forms, and the total calcium content is rich,and the calcium in mulberry leaves powder is more easily absorbed by the human body.