Background/purpose: With advances in medical technology, light therapy has attracted increasing attention as a non-drug treatment for depression. Methods of study: We conducted a scoping review to understand the efficacy and uses of light therapy as an intervention for depression. Results: Light therapy exhibits good results for seasonal affective disorder and non-seasonal affective disorder. Light therapy can simulate sunshine duration and alleviate the symptoms of seasonal affective disorder. It can also regulate the circadian rhythm to alleviate the symptoms of non-seasonal affective disorder. Conclusions: Light therapy has many applications as a non-drug treatment. Light therapy is an effective adjuvant treatment for depression patients as it can achieve therapeutic effects and improve patients' quality of life. The introduction of human factors and ergonomics and advanced optical techniques can allow light therapy to play dual roles of alleviating injury and treatment in depression and other psychological disorders.