An incubation study was carried out to assess the quality of the vermicompost and farmyard manure in terms of total nutrient content and microbial population count following inoculation of various microbial cultures. Azotobacter, Azospirillum and phosphate solubilizing bacteria (PSB) culture @ 0.2 % each was inoculated in different consortia to farmyard manure (FYM) or vermicompost and incubated for thirty days in a completely randomized design laboratory experiment maintaining moisture content at about 25±1 % (w/w). The population of Azotobacter, Azospirillum and PSB significantly increased in the composts by about 35 to 133% during the 30 days incubation period with different consortia. The C:N ratio reduced significantly in FYM and vermicompost after 30 days incubation due to significant decrease in total carbon content. The content of total N, P and K was not affected in vermicompost at 30 days after inoculation of microbial culture, but the same in FYM decreased significantly barring few occasions.