Abstract: Objective： To compare the short-term effects of Nd:YAG laser and fluor protector in the treatment of dentin hypersensitivity after periodontal initial therapy. Methods：42 cases of chronic periodontitis patients with dentin hypersensitivity after periodontal initial therapy (scaling and root planing, SRP), were randomly divided into two groups. Laser group (60 teeth): treated with Nd:YAG laser; Fluor protector group (60 teeth): fluor protector smeared. The degree of pain was recorded before and after treatment immediately, 1 week and 1 month later. Total effective rate was calculated to evaluate short-term clinical effect. Results： Immediately after treatment, the total effective rates of laser group and fluor protector group were respectively 95% and 93.33% (P＞0.05). One week later, the total effective rates of two groups were 91.67% and 90% (P＞0.05). A month after therapy, the total effective rate of laser group was 88.33%, whereas the total effective rate of fluor protector group was 78.33% (P＜0.05). Conclusions： There is no difference in treating dentin hyper sensitivity after SRP between Nd: YAG laser and fluor protector group within 1 week, but laser irradiation is superior in 1 month post-operative observation.