It is known in the literature that the incidence and prevalence of suicide and attempted suicide in psychiatric patients is significantly higher than in the general population. The paper examined risk factors for suicidal behavior in the category of admitted patients hospitalized with the diagnosis of sleep disorders and affective (Unipolar resp. Bipolar depression). Study activated by 80 patients, 40 in both diagnostic groups received treatment at the Special Psychiatric Hospital in Gornja Toponica near Nis. The work methodology used are: psychiatric interview, Hamilton Depression Rating Scale (HAMD), and the C-SSRS (Columbia-Suicide Severity Rating Scale)- assessment tool that assesses suicidal ideation and behavior. The study results show that there is a relationship between suicidal behavior (suicide attempts and suicidal ideation) and the diagnosis of bipolar affective disorder, positive history of previous suicide attempts, so that these factors are stronger, to the degree of suicidality higher. On this sample, clearly suicidal behavior, with the same purpose, intensity of suicidal thoughts and medical impairment after suicide attempts were significantly more frequent in patients with Bipolar Affective Disorder in the depressive phase of the illness. Patients with a previous suicide attempt, and poor personal and social circumstances had a higher rate of attempted suicide.