Cisplatin neurotoxicity was studied in rats by using electrophysiological and functional tests. The drug was injected intraperitoneally two times a week (1 mg/kg) up to a cumulative dose of 19.0 mg/kg body wt. At this dose the H-reflex-related sensory nerve conduction velocity was reduced. After cessation of drug administration, the H-reflex-related sensory nerve conduction velocity slowly improved. The motor nerve conduction velocity remained unaffected throughout the intoxication period and concentric needle investigation showed no signs of denervation. In addition, the sensorimotor response to a noxious stimulus presented locally to the foot sole was not affected by the cisplatin treatment. It is concluded that measurement of H-reflex-related sensory nerve conduction velocity is a useful and accurate tool in the evaluation of cisplatin neurotoxicity in rats.