Objective To explore the clinical efficacy of semiconductor laser and Beyond cold light in tetracycline tooth whitening. Methods A total of 78 patients with tetracycline teeth admitted to the Stomatological Center of Suining Central Hospital from November 2021 to January 2024 were selected as the research objects. They were divided into control group and experimental group by random number table method, with 39 patients in each group. The control group was treated with semiconductor laser bleaching, and the experimental group was treated with Beyond cold light whitening. The clinical efficacy, adverse reactions, satisfaction with tooth whitening maintenance, and periodontal indicators were compared between the two groups. Results There was no significant difference in total effective rate between the two groups immediately after treatment (P >0.05). There was no significant difference in total effective rate between the two groups after 6 months of treatment (P>0.05). The satisfaction of tooth whitening maintenance effect in the experimental group was better than that in the control group after 1 month and 3 months of treatment (P <0.05). After treatment, PLI, GI and SBI in the experimental group were lower than those in the control group (P<0.05). There was no significant difference in the incidence of adverse reactions between the two groups (P>0.05). Conclusion Beyond cold light is more effective than semiconductor laser in tetracycline tooth whitening, which can improve the satisfaction of patients with tooth whitening maintenance effect, and the periodontal level is better after treatment, and the treatment safety is good, which is worthy of clinical application.