Abstract Rheumatoid Arthritis is a systemic autoimmune inflammatory disease characterized by synovitis and serositis (inflammation of the linning surfaces of the joints, pericardium, pleura and rheumatoid nodules). This study was carried to determine the status of biochemical parameters i.e. calcium, phosphorus and calcium/phosphorus ratio in serum and synovial fluid of RA patients. A total of 66 RA patients were included in the study. Out of which 48(72.7%) were female patients of RA and 18(27.3%) were male patients of RA. Some normal individuals (n=25) were also investigated. The levels of serum calcium and phosphorus were found to be significantly (p<0.001) lowered as compared to normal individuals. A significant (p<0.001) decrease in levels of calcium and phosphorus in synovial fluid of RA patients was observed. Calcium/phosphorus ratio was also found to be lowered in RA patients. It was also observed that calcium/phosphorus ratio was more decreased in females as compared to males.