Cisplatin is a widely used chemotherapeutic agent, highly effective in the treatment of various types of human malignancies. The antitumor activity of cisplatin is attributed mainly to its ability to form adducts with DNA. Cisplatin may react with proteins and also with glutathione forming complex GS-Pt. This agent causes haematological, neurological toxicity and changes function of different cells. Recently, is has been reported that administration of sodium selenite reduces cisplatin toxicity without inhibiting the antitumour activity of cisplatin. This review focuses on the mechanism of cisplatin - induced cytotoxicity and the protective role of selenium.