An experiment was conducted to investigate the effects of earthworm activities on soil microbial biomass,activity(basal respiration) and community composition(sole-source carbon utilization,SCU) in a six years rice-wheat rotation system.Five treatments were included: control(CK),straw mulching(M),straw incorporation(I),straw mulching and earthworm inoculation(ME),straw incorporation and earthworm inoculation(IE).The presence of earthworms had significant effects on soil microbial biomass,microbial activity and the ability of carbon source utilization by microbe.Microbial biomass increased in the presence of earthworms irrespective of the way of straw application.Soil microbial activity,richness and biodiversity all decreased in the presence of earthworms under straw mulching method,and the reverse was true under straw incorporation method.It was indicated that soil microbial community composition changed significantly under straw application and earthworm activities using BIOLOG carbon utilization analysis.