Melasma is a common dermatological skin disease that can now be treated by fractional photothermolysis (fractional resurfacing). Past studies have shown that thermal spring water (TSW) spray can reduce local inflammatory symptoms after dermatological surgery, laser surgery or chemical peelings. The aim of this study was to evaluate the clinical efficacy and safety of spraying TSW post-fractional resurfacing treatment in patients with dermal melasma.