Objective To compare the influences on periodontal condition between self-ligating brackets and conventional brackets. Methods A total of 120 subjects (age range between twelve and sixteen) were selected which were averaged into four groups (C, S1, S2, S3) at random by different bracket types. Group C included 40 patients with conventionally-ligated bracket as control group, and the others (S1, S2, S3) included 40 patients respectively with self-ligating brackets as experimental groups. Before treatment and 1, 3, 6 months after beginning of treatment respectively, the periodontal parameters PLI, GI, PD were examined. Results There was no significant difference between the 4 groups between T0-T1. 3,6 months after the orthodontic treatment , no matter conventionally-ligated bracket or self-ligating brackets, the periodontal parameters PLI, GI of the tested teeth increased significantly than before, however, the values of PD did not show any significant difference. Three and six months after beginning of treatment, PL, SBI, PD between the conventional and self-ligating groups have significant differences (P＜0.05). There were no statistically significant differences at all the time intervals between the self-ligating brackets groups (P＞0.05). Conclusion The self-ligating brackets have an advantage over conventional brackets with respect to the periodontal improving of control of plaque and gingival bleeding, but not for periodontal pocket depth.