The prognosis of musculoskeletal sarcomas is related to appropriate management by specifically trained multidisciplinary teams. Musculoskeletal radiologists are responsible for the image-guided percutaneous biopsy of these tumors, which has a diagnostic accuracy of at least 80%. It is essential for radiologists to know: a) the limitations of percutaneous biopsy with respect to surgical biopsy; b) what should and should not be biopsied; c) how to appropriately plan percutaneous biopsy, with special attention to the route of approach, taking into account the compartmental anatomy and the route of approach after surgical treatment; and d) technical aspects of the procedure, like the area of the tumor to biopsy, the caliber of the needle, the number and length of the specimens to obtain to ensure optimal pathological diagnosis, and techniques in function of the imaging modality and bone penetration.