Objective To observe the curative effect of otoscopic underlay and interlay myringoplasty for chronic suppurative otitis media (CSOM).Methods Clinical data of 66 CSOM patients undergoing otoscopic myringoplasty with either underlay method or interlay method between June 2019 and June 2021 were retrospectively analyzed. Otoscopic type I myringoplasty with either underlay method or interlay method was performed by the same surgeon (33 cases in each group). The repair feature of tympanic membrane and hearing improvement between the two groups were compared.Results Satisfactory healing of perforation was achieved in 31 patients of the underlay group with a healing rate of 93.9%, and 32 of the interlay group with a healing rate of 97.0%. The preoperative and postoperative air-bone gaps (ABGs) in the underlay group were (21.76±9.43) dBHL and (15.97±8.60) dBHL with an increase of 6 dBHL on average (P=0.011), while those in the interlay group were (19.06±8.40) dBHL, (12.30±7.23) dBHL, and 7 dBHL respectively (P=0.001).Conclusions Otoscopic type I myringoplasty with either underlay method or interlay method can achieve an ideal tympanic membrane healing and hearing improvement indistinguishably. In addition, with less operation time and short postoperative hospital stay, otoscopic surgery has vast space for development.