A study was conducted at Maud T.E., Assam, India as part of FAO-CFC-TBI Project (2008-09 to 2012-13) to evaluate the quality of on-farm compost produced under different composting method and its effectivity on soil quality development. Comparative nutrient content in terms of N + P205 + K20 was highest in Novcom compost (3.98 %) followed by Biodynamic (3.56 %), Vermi (3.16 %) and Indigenous (2.96 %) compost. But comparative evaluation of microbial population (total bacteria, fungi, actinomycetes, ammonifiers, nitrifiers and phosphate solubilizing bacteria) in all the compost samples revealed distinctly different status of Novcom compost as compared to the rest. In case of vermi, Biodynamic and Indigenous compost, microbial population varied between 107 to 1012 c.f.u. where as that of Novcom compost varied from 1012 to 1016 c.f.u. The comparatively high microflora population in Novcom compost could be due to its intense biodegradation process, which led to their natural generation within compost heaps. Post compost application effectivity assessment revealed that Soil Development Index (SDI) was highest in case of Novcom compost treated plots (SDI : 57.83) followed by plots receiving Biodynamic (SDI : 28.22), Indigenous (SDI : 27.82) and Vermi (SDI : 23.36) compost respectively. Positive and significant (r = 0.54**) correlation of SDI with crop yield indicated that it can used as an effective tool to judge the soil quality in relation to crop performance as well as to assess the competence of soil management programme.