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BACKGROUND Psoralen and ultraviolet A (PUVA) phototherapy is associated with an increased risk of nonmelanoma skin cancers and may be associated with cutaneous melanoma in White populations. However, data on the safety of PUVA phototherapy in non-White populations are scarce. OBJECTIVE To assess the risk of nonmelanoma skin cancer and cutaneous melanoma among psoriasis patients receiving PUVA phototherapy. METHODS We conducted a nationwide Taiwanese cohort study spanning from 2001 to 2018 to assess the risk of PUVA phototherapy in relation to nonmelanoma skin cancer and cutaneous melanoma in psoriasis patients. RESULTS Among 13,245 psoriatic patients, PUVA phototherapy was associated with an increased risk of nonmelanoma skin cancer (adjusted hazard ratio [HR], 1.55; 95% confidence interval [CI], 1.03-2.32, P=0.03). The association remained consistent when considering the number of PUVA phototherapy sessions (adjusted HR, 1.006; 95% CI, 1.004-1.009, P<0.0001). Notably, neither PUVA phototherapy nor the number of PUVA phototherapy sessions revealed an increased risk of cutaneous melanoma (adjusted HR, 0.90; 95% CI, 0.24-3.42, P=0.87; adjusted HR, 1.000; 95% CI, 0.977-1.023, P=0.994, respectively). CONCLUSION These findings suggest that PUVA phototherapy was associated with an increased risk of nonmelanoma skin cancer but not melanoma in Asian psoriatic patients with Fitzpatrick skin phototypes II to V. For psoriasis patients who have received PUVA phototherapy, regular follow-up skin examinations are suggested.