Background This study aimed to evaluate the efficacy and safety of a dissolving microneedle (DMN)-encapsulated niacinamide skin patch to reduce facial hyperpigmentation. Methods A split-face study was conducted between April and June 2022 in 17 patients treated with a DMN-encapsulated niacinamide skin patch, which was applied only on the right side of the face, while the left face remained free of a pigmentation-improving agent. A topical moisturizer and physical sunscreen were applied on both sides of the face for 2 weeks. We compared both sides of the face 2 weeks after applying the skin patch using an automatic skin analysis device to investigate skin pigmentation. The melasma severity scores of both sides were evaluated before and 2 weeks after application. Results A significant difference in the epidermal pigmentation score between pre-treatment and 2 weeks after treatment was noted on the right side (P<0.05), but not on the left side of the face (P>0.05). A significant difference in the melanin score between pre-treatment and 2 weeks after treatment was noted on the right side (P<0.05), but not on the left side (P>0.05) of the face. There was no significant difference in the melasma severity score on either side of the face between pre-treatment and 2 weeks after treatment (P>0.05). Conclusions The application of a DMN-encapsulated niacinamide skin patch to improve skin pigmentation may yield good outcomes and provide comfort to patients without any complications.