This study investigates seasonal variations in the physico-chemical and bacteriological parameters of the Jojari River in the Salawas region of Jodhpur, Rajasthan, from April to September 2022. Monthly samples were analyzed for temperature, pH, TSS, TDS, and microbial indicators including total coliforms, E. coli, and fecal streptococci. Results showed significant water quality deterioration during summer, with temperatures up to 31°C, TSS peaking at 520 mg/L, and E. coli reaching 12,500 CFU/mL. Despite some dilution during the monsoon, microbial loads remained above safe limits due to runoff. A strong correlation was observed between TSS and bacterial counts, indicating the role of suspended solids in microbial persistence. The findings highlight the urgent need for seasonal water quality monitoring, wastewater management, and pollution control in semi-arid river systems