Septic arthritis presents with pain and swelling in the joint, and if untreated cases can lead to irreversible arthropathy and disability is an unusual complication during pregnancy and post-partum period. The morbidity is due to destruction of the articular cartilage resulting in impaired mobility of the joint. Severity depends upon the organism involved and host's own defences. Septic arthritis of the knee joint is very rare during post-partum period and very few cases have been reported so far. We report a rare case of post-partum Staphylococcal septic arthritis of the knee joint in a low risk woman, who was successfully treated