Introduction Suicide is a conscious and intentional destruction of one’s own life, which occurs as a result of mutual influence of a person’s disposition and motives (facts inspiring the commitment of suicide). It is well known that various diseases, including malignancies, could be important and in some cases the only motive for committing suicide. Objective The purpose of the study was to analyze in detail suicides of persons whose only motive was an established malignant disease. Method The analysis was performed using the autopsy material of the Institute of Forensic Medicine, School of Medicine, University of Belgrade, during the period from 1990 to 2004. The reports on performed medico-legal autopsies were used, as well as history data obtained from the family members of suicidal persons, investigation reports and the available medical documents. Results In 1931 cases there was established suicidal nature of a violent death. Neoplasms were the suicidal motive in 37 persons (1.9%). The basic characteristics of the analyzed sample were predominance of males (26:11, ratio 2.4:1), the age of over 70 years and the highest incidence of malignant lung and breast tumors. Almost all cases were the persons who underwent treatment for malignant neoplasms over a longer period of time. During 19 autopsies (51.3% out of 37), a progressive phase of malignancy was established, i.e. metastases. The data on prior oral announcement of suicide intention were obtained for 70.3% (26 cases), and on previous suicidal attempts only for 13.5% (5) cases. In the majority of cases (78.4%) the place of committed suicide was the person’s home. In 16 cases (43.2%) the suicide was committed with a firearm. Hanging as a manner of destroying one’s own life was chosen by 12 persons (32.4%), while other ways were less frequently used. Conclusion Although malignancies were not present with high incidence as a suicidal motive in our analyzed sample, such cases require particular care of health workers in order to enable the application of adequate measures in the prevention of suicides in persons with malignant diseases. The suicide analyses performed so far indicated that a malignant disease was the motive. Doctors have to show maximal interest for the patient. Prevention is crucial, so the patient should be provided with such surroundings in which the person will not feel alone and abandoned.