Soft tissue sarcomas (STSs) sometimes abut on adjacent bone or infiltrate into the bone itself. Bone invasions of STSs can be well evaluated using magnetic resonance imaging (MRI) scans. Osseous abutment, defined as loss of a normal soft tissue interface between the tumor mass and osseous cortex, cortical destruction, and cortical and medullary signal intensity change are assessed. In the equivocal cases, fixation to the underlying bone on physical examination and increased uptake of radioisotope on bone scan are also helpful to detect bone invasion. For proper surgical excision of STSs with bone invasion, part of the bone should be resected together, and an appropriate bone reconstruction will be necessary. On assessment of the extent of STSs abutting adjacent bone, a thorough preoperative evaluation of bone involvement status using physical examination and imaging studies including MRI is important for decision making. Here, I present a case of STS with osseous invasion. And I discuss the treatment strategy, basic principles and technical points in the management of STSs with osseous invasion.