Abstract:The active organic carbon in soils include microbial biomass carbon, water dissolved organic carbon, mineralizable carbon and so on. Earthworms, as one of important soil macro animals, and crop residues have great role in modifying the composition of soil active carbon. However, few studies were carried out in this area. Our ten weeks experiment in the lab was focus on the dynamic changes of biologically active organic fractions of soil such as microbial Biomass carbon (SMBC), water extractable organic carbon (WEOC) Carbohydrate (CHOC) and dissolved phenols (PEOC), which were affected by maize residues and earthworms (Metaphire guillelmi). Soil samples (orthic aquisols) were collected from Rugao County, Jiangsu Province. Treatments were: (1) no earthworms inoculation, no residues application (S); (2) earthworms inoculation only (SE); (3)suface application of residues only (SRC); (4) surface residues + earthworms inoculation (SRCE); (5) residues buried and mixed with soil only (SRM); (6) residues buried and mixed with soil + earthworms inoculation (SRCM). Result indicated that the inoculation of earthworms increased the content of SMBC, WEOC, CHOC and PEOC, and the differences among the treatments were significant when surface residues covered the ground. But the content of SMBC and CHOC decreased by 11.04% and 16.63% respectively, in the treatment of residues buried and mixed with soils. The possible reason may due to the ingestion of microbe and organic matter by earthworms. Both treatments of surface and buried application of residues had significant effects on all types of active carbon contents determined. Whether earthworm inoculation or not, comparing the effects of the residue application, the buried and mixed residues with soil had stronger effects on content of all composition of active organic carbon. Results of a three-way ANOVA showed the effects of earthworm inoculation, residues application and sampling time all had strong significant effects on results. The v of residues on content of WEOC, CHOC and PEOC were 82.35%, 62.53% and 7582% respectively. The results also had a uniform changing trend as the inoculation time. There were significant correlation with each other among WEOC, SMBC, CHOC and PEOC.