Treatment of patients with malign hematological diseases is directed to the apilation of antineoplastic drugs that have different chemical structure. Antineoplastic drugs that are used in the treatment of patients can effect contractility of miocards, its irritation and perfomance of stimulus. Malign hematological diseases seldom effect directly cardiovascular system; that is why the occurred changes are mainly consequence of toxic effects of antineoplastic drugs. The goal of the study: determine toxic effect of antineoplastic drugs to cardiovascular system. The autors were carrying out analysis of the cardiovascular system in patients with malign hematological disease. Besides clinical, laboratory findings, the following was used: electrocardiogram, radiogram of heart and lungs and heart echosonography when there was indication. Problem for clinical-hematologist is how to achieve, by therapy, maximum effect against stations of malignant process with minimal damages of healthy organs of the host. Reaction of patients to antineoplastic drugs is individual which requires daily assessment of cardiovascular system function and control must be directed to anamnesis data, regularity of blood pressure and heart rhythm, guality of sounds, occurrence of new sound phenomenom (murmurs) based on indication of electrocardiogram, radiogram and echosonography of heart.