The expression and prognostic significance of hepatocyte growth factor (HGF) and its receptor c-MET (MET proto-oncogene) was analysed in 96 cases of diffuse large B-cell lymphoma (DLBCL). Tissue sections were immunohistochemically stained for HGF and c-Met. The prognosis of HGF-positive and c-Met-positive cases was significantly worse than negative cases (HGF: P = 0·0036; c-Met: P = 0·0002). In addition, in the low-risk international prognostic index group, HGF-negative and c-Met-negative cases had a significantly better prognosis than positive cases (HGF: P = 0·0009; c-Met: P < 0·0001). Our results suggest that HGF/c-MET is a useful clinical marker of prognosis for patients with DLBCL.