Abstract: Objective To investigate the influence of periodontal non-surgical treatment on periodontal clinical parameters and OC in gingival crevicular fluid(GCF) of patients with aggressive periodontitis. Experiments To detect periodontal clinical parameters of 60 teeth from 20 cases of aggressive periodontitis before treatment and 4 weeks after periodontal non-surgical treatment. Assays of OC in GCF were performed by ECL. Results Level of OC was distinctly higher in experimental group than that in the control group; level of OC obviously reduced after teatment(p<0.05). Conclusion Periodontal non-surgical treatment can distinctly improve the clinical parameters and decrease the amount of OC in GCF of patients with aggressive periodontitis.