Abstract: Objective To investigate the correlation between vitamin D, bone alkaline phosphatase(BALP)contents and fracture healing speed in patients with radial and ulnar fractures. Methods The clinical materials of 90 patients with radial and ulnar fracture were retrospectively analyzed, and the contents of 25-dihydroxyvitamin D₃ ［25(OH)D₃］ and BALP were detected before surgery, 5 and 14 days after surgery. Based on the preoperative detection results, 26 patients with results less than 20% of the average value were taken as control group, and the patients with results over than 20% of the average value were taken as observation group. X-ray films were taken at 1 month and 3 months after surgery, and the fracture healing conditions of the patients were observed. The correlations between vitamin D, BALP contents and fracture healing speed in patients with ulnar and radial fracture were analyzed. Results The contents of 25(OH)D₃ and BALP decreased gradually before surgery and 5, 14 days after surgery in all the patients, and there were significant differences(P<0.05). The contents of 25(OH)D₃ and BALP in the observation group were significantly higher than those in the control group(P<0.01). The time of callus formation and fracture line disappearance in the observation group was significantly shorter than that in the control group(P<0.05). - Pearson correlation analysis showed that there were significant negative correlations between vitamin D, BALP contents and callus formation time, fracture line disappearance time(r=-0.687, -0.390, -0.806, -0.548, P=0.018, 0.002, 0.003, 0.037). Conclusion Vitamin D and BALP contents are related to fracture healing speed. The supplementation of exogenous vitamin D can shorten the healing time of fractures.