Objective:To investigate the prevalence of fever after intravenous injection of for the first time in osteoporotic patients who have or haven’t taken bisphosphonates orally.Methods:Bone mineral density measurement was conducted of the osteoporotic patients using dual-energy X-ray absorptiometry method,and according to the WHO diagnostic criteria for osteoporosis,the patient whose T score was less than -2.5 was defined as osteoporosis.The data of 113 osteoporotic patients who received intravenous injection of zoledronic acid in our hospital for the first time were used for analysis.Among them,35 who had the history of oral bisphosphonates were defined as group A,and 78 who didn’t have the history of oral bisphosphonates were defined as group B (control group).Moreover,we also compared the preva-lences of fever between the patients.Pearson chi-square test was used to investigate the association be-tween oral bisphosphonates therapy and prevalence of fever,and binary logistic regression was used to an-alyze the impact factors of fever after intravenous injection of zoledronic acid.Results:Among the 35 pa-tients who had the history of oral bisphosphonates,nobody had high fever,and 2 patients had low or mo-derate degree of fever (5.71%).Among the 78 patients who didn’t have the history of oral bisphospho-nates,33 patients had fever (42.3%),15 with low fever,and 14 with moderate degree of fever,and 4 with high fever.Pearson chi-square test showed that the prevalence of fever between group A and group B had significant difference,and that differences of prevalence of fever between the outpatients and the inpa-tients was not statistically significant.Binary Logistic regression analysis showed that oral bisphosphonates medication history was a protective factor of fever,and with the increasing of previous oral bisphosphonates for one month,there was a reduction of fever for 23.1%.Conclusion:Patients who have the history of oral nitrogenous bisphosphonates alendronate have a significant reduction in prevalence of fever after intravenous injection of zoledronic acid for the first time.That is,oral nitrogenous bisphosphonates alendronate history is a protective factor of fever for patients with intravenous injection of zoledronic acid for the first time.