The aim of this study was to investigate the differential effect of various delusion categories, namely, guilt, paranoid, impending disaster, and somatic on suicidal attempts in elderly patients experiencing unipolar psychotic major depression (PMD), because the evidence on this is scarce. The sample consisted of 65 consecutively admitted patients 60 years or older, experiencing PMD, and assessed by means of Structured Clinical Interview for DSM-4 (Patient Edition), Hamilton Depression Rating Scale, Mini-Mental Status Examination (MMSE), and by a physical impairment rating scale. Patients with guilt delusional beliefs had 5.31 times higher odds (95% confidence interval, 1.37–25.40) of a suicidal attempt than the patients without guilt delusional beliefs, controlling for sex, age, prior history of suicide attempt, MMSE, and hallucinations. In addition, 17 PMD patients with lifetime suicidal attempt compared with 48 PMD patients without lifetime suicidal attempt presented only higher age of disorder onset (p = 0.008). Of the four categories of delusions assessed, only guilt delusions were associated with an increased risk for suicidal attempt.