Background: Color vision deficiency (CVD) is a common congenital ophthalmic disease, and no effective therapeutic measures are currently available for this patient population. This study aimed to explore the efficacy of photobiomodulation (PBM) in CVD patients. Methods: A randomized controlled trial design was applied in this study, whereby 80 patients with red-green CVD were randomly divided into PBM treatment and control groups. Color vision was assessed after 1, 2, and 4 weeks of treatment. Statistical analysis of treatment was carried out using the Kruskal-Wallis test with Dunn's test for multiple comparisons using SPSS and R software. Findings: Compared to the control group, the color vision of CVD patients exhibited a significant improvement in the PBM treatment group for different parameters (Ps<0.05). Interpretation: PBM therapy could significantly improve color vision in patients with congenital CVD, especially in patients with green CVD.