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Aims Rhabdomyosarcomas of bone are extremely rare, with fewer than 10 reported cases. A very rare subtype of spindle cell/sclerosing rhabdomyosarcoma harbouring a FUS-TFCP2 fusion and involving both soft tissue and bone locations has been reported very recently. We report only the fourth case of this unusual, clinically aggressive rhabdomyosarcoma. Material and results A previously well 72-year-old male presented with a destructive lesion of the mandible. Morphological and immunohistochemical study of a needle biopsy and the subsequent resection showed a spindle cell rhabdomyosarcoma. RNA-seq, RT-PCR and FISH confirmed the presence of the FUS-TFCP2 fusion. Conclusions Spindle cell rhabdomyosarcomas carrying the FUS-TFCP2 fusion are very rare rhabdomyosarcoma variants with osseous predilection. The classification and differential diagnosis of this unusual molecular variant of spindle cell/sclerosing rhabdomyosarcoma are discussed.