Staphylococcus caprae is a catalase-positive, coagulase-negative coccus that has been originally isolated from goat milk. We describe the first case of an intra-articular empyema caused by S. caprae in an immunocompetent patient following arthroscopic cruciate ligament repair. The patient recovered completely after debridement and antibiotic therapy with cefazolin and amoxicillin, respectively. This case demonstrates that this organism may rarely cause serious nosocomial infections in immunocompetent adults.