Methyl acrylate is a widely used raw chemical materials and it is toxic in humans. In order to treat the methyl acrylate waste gas, a 3-layer BTF packed with ceramic particles and immobilized with activated sludge was set up. The BTF exhibited excellent removal efficiency that no methyl acrylate could be detected when EBRT was larger than 266 s and inlet concentration was lower than 0.19 g/m(3). The 1st layer performed the best at fixed inlet concentration of 0.42 g/m(3). PCR combined with DGGE was performed to detect the differences in different layers of the BTF. Phylum Proteobacteria (e.g. alpha-, beta-, gamma-, delta-) was predominantly represented in the bacterial community, followed by Actinobacteria and Firmicutes. Desulfovibrio gigas, Variovorax paradoxus, Dokdonella koreensis, Pseudoxanthomonas suwonensis, Azorhizobium caulinodans, Hyphomicrobium denitrificans, Hyphomicrobium sp. and Comamonas testosteroni formed the bacteria community to treat methyl acrylate waste gas in the BTF. (C) 2016 Elsevier Ltd. All rights reserved.