Purpose: Illness uncertainty pervades individuals' experiences of cancer across the illness trajectory and is associated with poor psychological adjustment. This review systematically examined the characteristics and outcomes of interventions promoting illness uncertainty management among cancer patients and/or their family caregivers. Methods: PubMed, Scopus, PsycINFO, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Embase, and Cochrane Database of Systematic Reviews were systematically searched for relevant literature.