There are few reports of tumours in bats, despite the fact that members of the Chiroptera order include 22.4% of all currently known mammal species. We now describe a case of malignant peripheral nerve sheath tumour (MPNST) in an adult female Seba's short-tailed bat (Carollia perspicillata) from a private zoo in Switzerland. The macroscopical and histological findings indicated that the MPNST originated from a dorsal spinal nerve root sheath in the lumbar region and metastasized to the spleen. Immunohistochemical labelling for glial fibrillary acid protein, S100 protein, neuron specific enolase and synaptophysin was negative. The cytoplasm of a few neoplastic cells labelled for smooth muscle actin and desmin. To our knowledge, this is the first report of a PNST in a member of the Chiroptera order.