Objective To compare the effects of semiconductor laser and Beyond cold light on tooth whitening. Methods A total of 110 patients who underwent tooth whitening in the Aviation General Hospital from June 2021 to June 2022 were selected as the research subjects, and they were divided into the control group (n =52) and the study group (n =58) according to different treatment methods. The control group received Beyond cold light treatment, and the study group received semiconductor laser treatment. The tooth color changes, dentin hypersensitivity, recurrence rate and adverse reactions were compared between the two groups. Results After treatment, the VITA shade guide score, a* value and b* value in the study group were lower than those in the control group, and the L* value was higher than that in the control group (P <0.05). The VAS score of dentin hypersensitivity in the two groups after treatment was higher than that before treatment, but that in the study group was lower than that in the control group (P <0.05). The recurrence rate in the study group (5.17%) was lower than that in the control group (17.31%) (P <0.05). There was no significant difference in the incidence of adverse reactions between the two groups (P >0.05). Conclusion Both semiconductor laser and Beyond cold light have tooth whitening effects, but semiconductor laser-assisted tooth whitening has a better effect, with lower dentin hypersensitivity and recurrence rate after treatment, and does not increase the incidence of adverse reactions, which is worthy of clinical application.