The relationships among bereavement, depressed mood, and immunologic patterns prognostic for the development of acquired immunodeficiency syndrome (AIDS) were determined in a sample of human immunodeficiency virus (HIV) seropositive gay men and a comparison group of HIV seronegative gay men. Immunologic parameters were assessed in 45 men who had recently experienced the deaths of close friends and 45 matched nonbereaved men. No immune differences were found between bereaved and nonbereaved men. Among the HIV seropositive nonbereaved men, higher depressed mood was significantly associated with fewer CD4 (helper/inducer) T lymphocytes, more activated CD8 (suppressor/cytotoxic) T cells, and lower proliferative responses to the mitogen phytohemagglutinin. In summary, HIV seropositive men who reported higher levels of depressed mood not associated with bereavement demonstrated immunologic patterns consistent with HIV activity and progression.