This single-blind randomized controlled clinical trial aimed to compare the effects of hypochlorous acid, hyaluronic acid, and chlorhexidine mouthrinses on palatal donor site healing following free gingival graft surgery. Fifty-four patients requiring free gingival graft surgery were randomly assigned to one of three mouthrinse groups. Clinical wound healing, wound dimensions, epithelialization, tissue consistency, bleeding control, and postoperative pain were evaluated during a 28-day follow-up period. The findings of this study may contribute to the identification of an effective postoperative mouthrinse for improving palatal donor site healing and patient comfort.