Objective To explore the effects of Saccharomyces boulardii combined with vitamin AD on bone metabolism and bone mineral density in children with vitamin D deficiency rickets.Methods Sixty-eight children with vitamin D deficiency rickets treated in a hospital in Pingdingshan from March 2017 to March 2020 were randomly divided into control group and experimental group

with 34 cases in each group.The children in the control group were treated with vitamin AD orally

and the children in the experimental group were treated with Saccharomyces boulardii on the basis of the control group.Both groups were treated for 4 weeks.The levels of plasma trace elements

bone mineral density and serum bone metabolic indexes were compared between the two groups before and after treatment.Results The levels of plasma calcium（Ca）

phosphorus（P） and zinc（Zn） in both groups after treatment were higher than those before treatment

and those in the experimental group were significantly higher than those in the control group

and the differences were statistically significant（P<0.05）.The levels of serum osteocalcin（BGP）

bone alkaline phosphatase（BALP） and urinary deoxypyridinoline（DPD） in the two groups after treatment were higher than those before treatment

and those in the experimental group were significantly higher than those in the control group

and the differences were statistically significant（P<0.05）.The bone mineral density of ulna and radius in both groups after treatment was higher than that before treatment

and that in the experimental group was higher than that in the control group

and the difference was statistically significant（P<0.05）.Conclusion Saccharomyces boulardii combined with vitamin AD can effectively promote the absorption of vitamin D and calcium

increase the level of bone mineral density

improve the index of bone metabolism and promote bone synthesis in children with vitamin D deficiency rickets.