Only a few human malignant peripheral nerve sheath tumour (MPNST)-cell lines have been reported, and their characteristics have not been fully established. In this study, we established a new human cell line, HS-Sch-2, from an MPNST of the ordinary type which arose in a 54-year-old woman without von Recklinghausen's disease. This cell line was characterized by chromosome analysis, immunohistochemistry, ultrastructural examination, and direct sequencing of the p53 gene. The HS-Sch-2 cells have grown for more than 48 months in vitro, and exhibited hypotriploid karyotypes with complex chromosome abnormalities lacking a specific pattern. Histological features of the heterotranplanted nude mouse tumours were essentially the same as those of the original MPNST, with positive reactions for S-100 protein and neuron-specific enolase but not for epithelial membrane antigen, fibronectin or CD34. Ultrastructural examination in vivo revealed intricate interdigitation of long cytoplasmic processes and basal lamina-like structures. In addition, direct sequencing of the p53 gene detected a point mutation from CGT to CAT at codon 273 in exon 8. This HS-Sch-2 cell line, which exhibits distinctive morphological characteristics of MPNST and a p53 point mutation, will be useful for biological and pathological investigations of MPNST.