Aims: Crusts forming at the surface of liquid manure (slurry) during storage have been shown to harbour a potential for mitigating CH₄ emissions. This study investigated the microbial community in surface crusts, with a focus on micro-organisms related to CH₄ metabolism. Methods and Results: Microbial communities in four crusts from cattle and swine slurries were investigated using denaturing gradient gel electrophoresis and tag-encoded amplicon pyrosequencing. All crusts had distinct compositions of bacteria and archaea. The genera Methylobacter, Methylomicrobium, Methylomonas, and Methylosarcina of Type I, and Methylocystis of Type II, dominated the methane-oxidizing bacteria (MOB) community, whereas Methanocorpusculum was the predominant methanogen. Higher numbers of operational taxonomic units (OTUs) representing Type I than Type II MOB were found in all crusts. Potential CH₄ oxidation rates were determined by incubating crusts with CH₄, and CH₄ oxidization was observed in cattle, but not in swine slurry crusts. Conclusions: Slurry surface crusts harbour a diverse microbial community. Type I MOB are more diverse and abundant than Type II MOB in this environment. The distinct CH₄ oxidation rates could be related to microbial compositions. Significance and Impact of the Study: This study is the first to present the overall microbial community structure in slurry surface crusts. A better understanding of microbial community in surface crusts could support strategies for mitigation of CH₄ emissions from livestock manure management.