Objective To investigate the effect of platelet-rich fibrin(PRF) pulp revascularization in young permanent teeth with periapical disease, and evaluate the effect of PRF on pulp viability and root canal calcification. Methods 104 young patients with periapical permanent teeth(12~18 years old) were randomly divided into observation group(52 cases with 66 teeth) and control group(52 cases with 61 teeth). The observation group was treated with PRF revasectomy, and the control group was treated with classical revasectomy. The therapeutic effects of the two groups were compared, including symptom relief and improvement of periapical imaging indexes. Pulp vitality was evaluated by thermal and cold stimulation and electrical measurement, and root canal calcification was evaluated by X-ray examination. Visual pain analogue scale(VAS) score and gingival fluid-related growth factor (bFGF) -vascular endothelial growth factor(VEGF) concentration were measured. Results The therapeutic effect of the observation group was significantly better than that of the control group (98.48% vs 90.16%)(P<0.05). At 12 months after surgery, the proportion of detectable pulp vitality in the observation group was higher than that in the control group (P<0.05), while there was no difference in root canal calcification rate between the two groups (P>0.05). Periapical imaging indexes in the observation group were significantly improved, and the root canal wall thickness and crown root length in the observation group were higher than those in the control group after treatment (P<0.05). At 2, 8, and 24d after treatment, the VAS scores of the observation group were lower than those of the control group (P<0.05). At 6 months after treatment, VEGF and bFGF concentration in observation group was higher than that in control group (P<0.05). Conclusion The application of pulp blood revasulation in PRF young permanent teeth with periapical root disease can effectively promote the recovery of pulp vitality, and promote the increase of root canal wall thickness and tooth length