Loneliness and social isolation, particularly in the older adult, have been shown to influence psychosocial well-being. Loneliness has been related to chronic illness and self-rated health in older adults, and researchers suggest there is an important relationship between loneliness and psychological well-being in older adults particularly in the area of depression. This study investigated relationships between loneliness, health, and depression in 217 older men (> 65 years). Participants completed self-report measures of loneliness, social support, depression, and physical health. Regression analysis showed that a diagnosis of illness or disability was unrelated to depression, however self-reported health was associated with depression, with those reporting poorer health experiencing greater depression. Social support variables were unrelated to depression. The most significant relationship to depression was that of loneliness, with lonelier men reporting higher scores on the Geriatric Depression Scale (GDS). Although research suggests that depression is often a response to declining health and functional impairment in the older adult, the present findings suggest that social isolation may also influence the experience of depression. Age-related losses such as loss of professional identity, physical mobility and the inevitable loss of family and friends can affect a person's ability to maintain relationships and independence, which in turn may lead to a higher incidence of depressive symptoms.