The study on microbial mechanism of straw decomposition process is the theoretical basis of regulation straw returning and enhancing of fertility on farmland. Reciprocal translocation experiment was set to investigate the changes of metabolic activity (expressed as AWCD, Average Well Color Development) during decomposition in Phaeozem, Cambisol and Acrisol under cold temperate, warm temperate and mid-subtropic climate conditions. Litter bag method avoiding soil entering was used to identify microbial communities responsible for straw decomposition. The results showed that the AWCD decreased with the increase of temperature and rainfall during half and one year decomposition. AWCD in 0.5 year showed that Hailun (0.765±0.060) > Fengqiu (0.737±0.165) > Yingtan (0.326±0.076), AWCD in 1 year showed that Hailun (0.630±0.092) > Fengqiu (0.319±0.096) > Yingtan (0.291±0.029).However the tendency was weak after two-year decomposition. Climate condition is the key factor that influenced the microbial carbon utilization activity. In addition, by principal component analysis, the microbial metabolic properties in Hailun and Fengqiu were quite different from that in Yingtan after 0.5 year, and the microbial metabolic properties in Fengqiu and Yingtan were quite different from that in Hailun. After two-year decomposition the microbial metabolic properties became similar under different climate conditions, which all had largely utilization to nitrogen compounds.