A total of 44 isolates were isolated from different ecosystems viz., Marine, Match factory, paper effluent, tannery effluent, beverage waste, alkaline and rhizosphere soil. Out of 44 isolates characterized, 24 isolates were screened based on their efficacy to reduce the pH of the growth medium from pH 8.0 to ≤ pH 4.5, within 5 days of incubation. The screened isolates were estimated for sulphate production and phosphate solubilisation. In vitro sulphate production from elemental Sulphur (Starkey media) was found to be highest for VSS4 (72 mg 100 ml-1) and the least for VST4 (35 mg 100 ml-1). The isolate VSS4 recorded the highest P- solubilization of 26 mg 100 ml-1 and the lowest Phosphorous solubilization was recorded by VSS6 as 11 mg 100 ml-1 of Pikovoskaya broth. Morphologically, most of the isolates were Gram positive, rod shaped; smooth, concentric and white color colonies. Species diversity, phylogenetic affiliations, and environmental occurrence patterns of Sulphur oxidizing bacteria were investigated by Intrinsic antibiotic resistance (IAR) profile, Amplified Ribosomal DNA Restriction Analysis(ARDRA)and 16S ribosomal RNA( rRNA) gene sequence, phylogenetic tree analysis.