Abstract: The present study has been conducted on the enrichment of biogas slurry vermicompost with microbial inoculants Azotobacter chroococcum and Bacillus megaterium, optimization of inoculum level and time inoculation during vermicomposting along with the survival rate of each microbial inoculant, the total microbial population and their correlation during the storage. On 0, 10, 20 and 30th day of inoculation showed decrease in the viable population of A. chroococcum and B. megaterium inoculated at the rate of 30, 35 and 40 mL-1 175 g of substrate, towards the progression of storage period of vermicompost, uniformly. The change of A. chroococcum and B. megaterium in the vermicompost (at 30, 35 and 40 mL-1 175 g substrate) with reference to the storage period (180 days) showed highly significant negative correlation (p<0.001). In all the four treatments, the viable population of A. chroococcum and B. megaterium at the rate of 30, 35 and 40 mL-1 175 g substrate from 0th day (after harvest) onwards showed statistically significant decline with that of storage period of vermicompost. This trend was observed uniformly for both the microbial inoculants, inoculated on 0, 10, 20 and 30th day of vermicomposting. In the present study, total microbial population in A. chroococcum and B. megaterium inoculated vermicompost was high during the initial phases of storage and then total microbial population declined towards the end. The vermicompost inoculated on 20th day of vermicomposting with A. chroococcum at the rate of 35 mL-1 175 g of substrate showed 11, 9, 8, 6, 3 and 0x107 cfu g-1 population of total microorganisms, respectively during 0, 15, 45, 75, 105 and 135th day of storage. Similar trend of results were obtained for B. megaterium inoculated vermicompost suggesting that the overall maintenance of total microbial population in vermicompost is similar in the vermicomposts with any microbial inoculants.