Tropical agricultural soil is facing a problem; the loss of soil organic matter (SOM) leads soil fertility degradation. Effects of agricultural managements on decomposition of SOM are linked to decomposer activities. Fungal-based energy channel in soil will moderate decomposition and fungi are the most important agents in the process of SOM formation and stability. Our objectives were to determine the effects of agricultural management on litter decomposition rate and microbial community composition in replicated field experiment, where conventional-till and no-till and presence or absence of mulch are the factors. We found that mulching suppressed decomposition rate of sugarcane leaf litter. Microbiological parameters were influenced by the managements and showed some variations depending on the stage of litter decomposition. At the initial stage, mulching decreased fungal diversity. At the intermediate stage, bacterial biomass and fungal diversity were higher in no-till, while fungal biomass was positively affected by mulch. At the later stage, bacterial and fungal biomass, and fungal to bacterial ratio (F/B) were higher in no-till. There were significant correlations between decomposition rate and fungal biomass and F/B in the intermediate stage. Overall, mulching and no-till increased microbial biomass and F/B.