OBJECTIVES/HYPOTHESIS: To evaluate the potential efficacy of steroid-soaked, absorbable calcium alginate nasal packing following endoscopic sinus surgery. STUDY DESIGN: Prospective, randomized, single-blinded, placebo-controlled trial. METHODS: Twenty-two patients (44 nostrils) who had chronic rhinosinusitis with polyps underwent bilateral endoscopic sinus surgery. Only those with an intersinus difference in Lund-Mackay severity score of 1 or less were included. In each patient, one randomly selected nostril was packed with calcium alginate soaked with 2 mL of triamcinolone (40 mg/mL) (triamcinolone group), whereas the contralateral nostril received an identical packing soaked in 2 mL of normal saline (saline group). Two independent investigators blinded to the packing allocation scored the surgical field using the validated Perioperative Sinus Endoscopy (POSE) scores 1, 4, and 8 weeks after surgery. RESULTS: All 44 nostrils were analyzed; the Lund-Mackay scores did not differ significantly between the groups before surgery. Eight weeks after surgery, the total POSE scores were significantly lower in the triamcinolone group (P = .014). The POSE scoring parameters were then compared between groups, and the following variables were significantly different: middle turbinate synechiae with the lateral wall (P = .037), polypoid degeneration of the ethmoid cavity (P = .006), and sphenoid sinus severity (P = .036). CONCLUSIONS: This study demonstrated that steroid-soaked, absorbable nasal packing can be used to enhance wound healing after endoscopic sinus surgery and to prevent polypoid changes in the nasal mucosa. LEVEL OF EVIDENCE: 1b. Laryngoscope, 128:311-316, 2018.