Earlier studies revealed that renal function is reduced in non-cancer patients with a malnutritional status. We have studied the effect of nutritional status on renal function in 46 patients with disseminated non-seminomatous testicular cancer treated with combination chemotherapy including cis-diammine dichloroplatinum (cDDP) according to the Einhorn regimen. The renal function was expressed as glomerular filtration rate (GFR), effective renal plasma flow (ERPF), and filtration fraction (FF) measured by radioisotope infusion methods. Nutritional assessment of the patients was performed by means of three nutritional parameters: weight-for-height index (WHI), creatinine height index (CHI), and serum albumin concentration (Salb). The patients were also divided into two groups: group 1, patients with a sufficient nutritional status, defined as patients with only one abnormal nutritional parameter or none at all (n = 30); group 2, patients with an insufficient nutritional status, defined as patients with two or three abnormal nutritional parameters (n = 16). Median values of WHI, CHI and Salb in group 2 patients were significantly lower than the median values in group 1. Before treatment no correlation was found between the individual nutritional parameters and GFR, ERPF and FF respectively. The median GFR, ERPF and FF of both group 1 and group 2 did not differ significantly. Although the renal function of the total group of patients was reduced as a result of cDDP, this reduction was not influenced by the individual parameters and not higher in the group with an initially insufficient nutritional status. In this study no relation was found between nutritional status and renal function of patients with disseminated non-seminomatous testicular cancer.