ABSTRACT Objectives This study examines the associations of cancer death and aspects of the 24-h circadian rest-activity rhythm (RAR) on depression symptoms in older spouses. Methods Participants included 46 adults aged 60–94 years (M = 73 years) who experienced the death of a spouse. We tested a multivariate model using cancer death (vs. non-cancer death) and RAR variables as correlates of depression symptoms while controlling for age, sex, physical illness burden, and preparedness for death. We also present a case example to describe the behavioral activity patterns of a participant bereaved by cancer. Results Cancer death was associated with elevated levels of depression symptoms. However, the timing of the RAR moderated this association. Cancer bereavement was associated with depression symptoms when participants “settled-down” after 11:00 PM. The case example illustrates how intrusive thoughts about death quality impacts a widower’s drive to stay busy with daily activities. Conclusions Settling down earlier in the evening is important for older spouses bereaved by cancer, in terms of fewer symptoms of depression. Clinical implications Objectively specifying the activity patterns of older spouses bereaved by cancer is a promising avenue for interventions that aim to reduce depression symptoms.