Osseous and cartilaginous soft tissue tumours are a heterogenous group of neoplasms characterised by the presence of an osseous or cartilaginous component. Mineralisation of the osseous or cartilaginous component is a common finding amongst these lesions, presenting as calcification/ossification on radiological imaging. This pictorial review examines the key imaging findings and characteristics of osseous and cartilaginous soft tissue tumours with a focus on the distinguishing features which can help the radiologist to differentiate benign and malignant lesions. All examples provided are of histopathologically proven cases seen in our tertiary referral soft tissue sarcoma centre. (c) 2024 The Royal College of Radiologists. Published by Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.