Subcutaneous emphysema of lower extremity is a rare disease entity. Crepitation and swelling on physical examination and gas on radiographs raise the concern of infection due to the presence of gas gangrene forming organisms. Therefore, delay of diagnosis and appropriate management can be a major predisposing factor for sepsis and further associated high mortality. We experienced a rare case of subcutaneous emphysema of the right lower extremity after knee arthroscopy; life-threatening infection was ruled out by physical examination and laboratory testing. The patient recovered uneventfully with conservative management. Therefore, we report on this case with a review of current literature.