In tropical forests, the stage of ecological succession influences the nutrient cycling. This study aimed to analyze soil fauna community structure, composition, and leaf litter decomposition in fragments of intermediate-successional and late-successional Submountainous Seasonal Semideciduous Forest (ISF and LSF, respectively). We used a square metal frame to collect 10 samples of the leaf litter layer and surface soil (0.00-0.05 m depth) from each area in the wet and dry seasons. Soil fauna individuals were then extracted using a modified Berlese-Tüllgren funnel. For analysis of leaf litter decomposition, 15 litter bags containing 30 g of senescent leaves were randomly placed on the forest floor of each area in the dry season, and three bags were collected after 60, 90, 120, 150, and 180 days. LSF presented higher value of richness and was more associated with Diptera and Formicidae. There was no clear pattern in evenness and diversity with successional stage. The dissimilarity between ISF and LSF in terms of soil fauna community was greater in the dry season. Litter decomposition was almost identical in both areas.