Seasonal fluctuations can influence many biotic and abiotic parameters in wetland environments. Present research on wetlands do not serve as a comprehensive model for understanding these seasonal influences, especially in Northeast India, where wetland ecosystems remain understudied. That being, our study investigated the seasonal, spatial, depth-wise variations of enzyme activity (xylanase, invertase, and cellulase), microbial community, and heavy metal concentrations [chromium (Cr), cadmium (Cd), lead (Pb), and iron (Fe)] in the sediments of Deepor Beel. Our results show, seasons rather than sediment layers influence all parameters. Enzyme activities peaked during post-monsoon (POM), with xylanase showing highest activity throughout (0.01-132.94 mmol/min/g). Culture independent bacterial diversity study based on next generation sequence (NGS) analysis revealed a steady decrease in unique amplicon sequence variants (ASVs) from pre-monsoon (PRM) (31), followed by POM (22) and finally monsoon (MON) (2). Bacteria consistently outnumbered archaea throughout the study. Heavy metals peaked during PRM, with Fe reaching 1416-1200 mg kg