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Municipal solid waste (MSW) landfills are the third largest anthropogenic source of methane (CH4) emissions in the United States. Part of the CH4 generated in landfills is converted to carbon dioxide (CO2) by CH4-oxidizing bacteria (MOB) present in the landfill cover soil, whose activity is controlled by various environmental factors including temperature. As landfill temperature fluctuates substantially due to seasonal variations and series of reactions during waste decomposition, which may affect the microbial activity and thus, the rates of CH4 oxidation. This study aims at analyzing the effect of temperature on CH4 oxidation potential and microbial community structure of methanotrophs in laboratory-based microcosm studies on landfill cover soil. Landfill cover soil samples were incubated at selectively two temperatures 23C and 50C, and rates of CH4 oxidation were measured, and microbial community structure was analyzed using shotgun metagenome sequencing. CH4 oxidation occurred at both temperatures in soil microcosm tests with highest activity at 23C. A corresponding shift in the soil microbiota was observed, with a transition from mesophilic to thermophilic methanotrophs with increased incubation temperature. The study shows that temperature is a critical factor affecting rates of CH4 oxidation in landfill cover soil, and the changing rates of CH4 oxidation are in part driven by shift in the methylotroph community.