Objective To explore the association between serum FGF23 and Klotho protein,and bone mineral density in maintenance hemodialysis (MHD) patients.Methods A total of 125 MHD patients admitted in the Hospital between January 2015 and November 2015 was enrolled.Their bone mineral densities of femur neck and lumbar spine were studied by dual-energy X-ray absorptiometry.These patients were divided into three groups as normal,osteopenic and osteoporotic,according to World Health Organization criteria based on bone mineral density T scores.Levels of serum FGF23,Klotho protein and 1,25(OH)2VitD3 were measured by ELISA.The parameters including calcium,phosphorus,and parathyroid hormone were assessed.Results The incidences of osteopenia and osteoporosis at the femur neck and lumbar spine in MHD patients were 82.40％ and 56.00％ respectively.No significant difference was found in the levels of serum FGF23 among normal,osteopenic and osteoporotic groups on the basis of femur neck and lumbar spine bone mineral density (P ＞ 0.05).No correlation was found between FGF23 and bone mineral density.There however were significant differences in the levels of serum Klotho protein among three groups on the basis of femoral neck bone mineral density (P ＜ 0.05).And the levels of Klotho protein in the osteoporotic group [(387.172±54.137) ng/L] were significantly decreased than those in normal group [(429.883±41.776)ng/L] and osteopenic group [(410.598±61.056) ng/L] (P ＜ 0.05).There were also significant differences in the levels of serum Klotho protein among three groups in terms of lumbar spine bone mineral density (P ＜ 0.05),while the levels of Klotho protein in the osteopenic group [(387.263 ± 53.255) ng/L] were significantly decreased than those in normal group [(417.108±56.179) ng/L] (P＜ 0.05).A positive correlation was found between Klotho protein and bone mineral densities of femur neck and lumbar spine.Multiple linear regression analysis showed that one of the main factors influencing the degree of bone mineral density in MHD patients was Klotho protein.Conclusions CKD-MBD with low BMD is common and widespread in hemodialysis patients.FGF23 has no direct effect on bone mineral density in MHD patients;while Klotho protein is correlated with the severity of bone mineral density.High-level Klotho protein may reduce the severity of CKD-MBD with low BMD in MHD patients.