Effect of application of arbuscular mycorrhizal fungi (AMF), phosphate-solubilizing bacteria (PSB), general bacteria and fungi (GBF) and amendments with farmyard manure (FYM), lime, top soil was studied in a pot experiment for coalmine overburden dump (OBD) spoils 1-and 5-year (yr) of Tikak Colliery, Assam, India on biomass production of Crotalaria striata DC and contribution to physicochemical and microbial properties of colliery spoils. AMF colonized in plant roots and increased above ground biomass in inoculated pots. AMF spore numbers increased many folds at harvest in the inoculated pots in 1-yr OBD spoil in comparison to the number of spore inoculated to them. The treatment combination Lime+ AMF+ FYM had favorable effect on biomass production both in 1-yr and 5-yr OBD spoils. Dual inoculation of AMF+ PSB was also found effective on plant growth. Plant growth was poor in 5-yr OBD spoil than that of 1-yr OBD spoil irrespective of the treatment combination applied. This could be reflection of more harsh condition for plant growth in 5-yr OBD spoils with very high level of H+ ions. Amendment with topsoil of natural forest was also effective in improving plant growth in coalmine spoils. The best treatment combination for biomass production was also superior in improving physico-chemical and biological properties of colliery spoils. lime, fertilizer, organic matter and soil cover on mine waste and combination of soil cover and soil amendments (Zak and Parkinson 1983, Pichtel, 2005, Perez-de-mora et al. 2006, Neagoe et al. 2005, Sydnor, et al. 2002). Microbial amendments such as arbuscular mycorrhizal fungi (AMF) inoculum may also be useful in speeding up revegetation on coal mine spoils (Danielson et al. 1979, Daft et al. 1976 and Hazarika et al. 2004). Although, role of indigenous microorganisms of mine waste has been studied extensively in relation to sulphide mineral oxidation to acidity generation and reduction reactions ameliorating polluted mine water (Johnson, 2005), there has only been few systematic research carried out to determine the usefulness of rhizosphere microorganisms on speeding up revegetation of coalmine waste (Banerjee et al. 2000, Kumar and Jena, 1996). Our previous studies indicated the natural colonization of vegetation and colonization of plant roots by AMF in the coal mine overburden dump of