Abstract: Riparian wetland, the transitional zone of river and terrestrial ecosystems, is a potential hotspot for microbial methane production and oxidation. Here, a 13CH₄-based stable isotope nucleic acid probe (DNA-SIP) microcosm incubation experiment combined with high-throughput sequencing and chemical analysis was employed to reveal the methane oxidation potential and active aerobic methane-oxidizing microorganisms in sediment collected from a riparian wetland soil of the Jialing River (Nanchong section). The results showed that the soil methane oxidation rate was 11.94 μg g^-1 d^-1 after incubation with 6% (v/v) CH4. Analysis of the pmoA gene distribution in DNA obtained by ultra-high speed density gradient centrifugation showed that the DNA of the aerobic methane-oxidizing bacteria was significantly labeled with 13C. Sequencing of the 13C-labelled DNA revealed that methane-oxidizing bacteria (MOB) belonging to Type I, and Type II dominated the aerobic methane oxidation process. Type I MOB accounted for 78.49% of the labelled MOB, which including Methylomicrobium, Methylogaea, and Crenothrix. Methylomicrobium accounted for 61.37% of the labelled Type I MOB. Methylocystis affiliating to Type II MOB was the main responder in methane oxidation in the soil. In addition, FAPROTAX functional annotation of 13C-DNA showed that the function of microbial communities involved in the carbon and nitrogen cycles were stimulated, such as chemoheterotrophy, methanol oxidation, methyl compound metabolism, and nitrogen fixation. This result suggested that microbial methane oxidation could be correlated with other biogeochemical cycling processes. This study highlighted that the aerobic methane oxidation in the riparian wetland soil was performed by a variety of metabolically flexible microorganisms, and provided basic data for physiological ecology study of methanotrophs in riparian wetlands.