Abstract Background Kingella kingae is the second most common pathogen causing paediatric arthritis and is described to be the causative bacteria in some paediatric osteomyelitis. Its microbiological detection is particularly difficult due to its slow growing. To our best knowledge this is the first case description of osteomyelitis pubis caused by this microorganism. Case presentation We report the unusual case of pubic osteomyelitis with soft tissue abcess caused by Kingella kingae in an adult patient of 66 years with a history of end-stage renal disease and breast carcinoma. Diagnosis was based on imaging and the microorganism was isolated from Computed Tomography-guided aspiration of synovial fluid. The infection resolved completely after twelve weeks of treatment with oral amoxicillin. Conclusion This case description highlights the importance in osteoarticular infections of systematic inoculation of synovial liquid in BACTEC vials to optimise the detection of causative organisms, which can necessitate specific treatments.