Objective To investigate the diagnostic value of excretion rate of deoxypyridinoline(DPD) in urine and bone-specific alkaline phosphatase(BAP) in serum for osteoporosis and the correlation between the 2 indexes.Methods The level of Ca2 ,P,alkaline phosphatase(ALP),BAP in blood,DPD,Cr in urine and bone mineral density(BMD) of the first to the fourth lumbar vertebrae were measured in seventy-three patients with osteoporosis,then the results were compared to those from fifty healthy subjects.Results The level of BAP and excretion rate of DPD in patients increased evidently in comparison with the healthy subjects groups(P<0.01),and there was a great difference between the results before and after treatment(P<0.01).There was positive correlation between the levels of BAP and DPD/Cr.Conclusions The determination of BAP and DPD/Cr is sensitive,and more convenient and economical than BMD,so BAP and DPD may be useful as diagnostic indexes for osteoporosis.