Abstract Background: Endoscopic sinus surgery (ESS) has become the treatment of choice for nasal polyposis and chronic rhinosinusitis that cannot be adequately managed with medical therapy. Nasal packing is usually placed after ESS to prevent synechiae formation and postoperative bleeding and to support wound healing. Objectives: This study was done to evaluate the effect of different materials on the formation of synechiae and excessive granulation tissue in the middle meatus in patients who had undergone ESS. Methods: A total of 90 patients who had undergone ESS were studied prospectively. At the end of ESS each patient was packed with one of the three different materials randomly. The outcome variable was the formation of synechiae and excessive granulation tissue in the middle meatus, which was identified from endoscopic evaluations performed 3–4 weeks and 10–12 weeks after surgery. Results: We observed significant intergroup differences in the effect on the formation of synechiae in the middle meatus. The nasopore group was superior to the other two groups and there is a significant reduction in synechiae formation in the nasopore group than both other groups. Conclusion: Among patients who had undergone ESS for rhinosinusitis with or without polyps, the incidence of synechiae and excessive granulation tissue in the middle meatus in the patients who received nasopore packing was less to that of synechiae in the patients who received merocel and mitomycin C.