Cardiotoxicity is a widespread complication of anticancer therapy. One of the most difficult manifestations of cardiotoxicity is cardiac arrhythmias. The incidence of arrhythmias in cancer patients has not been fully established because most studies had insufficient number of patients. Establishing a causal relationship between anticancer drugs and specific arrhythmias also presents certain difficulties. The purpose of this review is to analyze the modern data on the incidence and clinical course of arrhythmias in patients taking anticancer therapy.