Objective Cancer is associated with negative health and emotional outcomes in those affected by it, suggesting the need to better understand the psychosocial determinants of illness outcomes and coping. The common sense model is the leading psychological model of self‐regulation in the face of illness and assumes that subjective illness representations explain how people attempt to cope with illness. This systematic review and meta‐analysis examines the associations of the common sense model's illness representation dimensions with health and coping outcomes in people with cancer. Methods A systematic literature search located 54 studies fulfilling the inclusion criteria, with 38 providing sufficient data for meta‐analysis. A narrative review of the remaining studies was also conducted. Results Random‐effects models revealed small to moderate effect sizes (Fisher Z) for the relations between illness representations and coping behaviors (in particular between control perceptions, problem‐focused coping, and cognitive reappraisal) and moderate to large effect sizes between illness representations and illness outcomes (in particular between identity, consequences, emotional representations, and psychological distress). The narrative review of studies with insufficient data provided similar results. Conclusions The results indicate how illness representations relate to illness outcomes in people with cancer. However, more high‐quality studies are needed to examine causal effects of illness representations on coping and outcomes. High heterogeneity indicates potential moderators of the relationships between illness representations and health and coping outcomes, including diagnostic, prognostic, and treatment‐related variables. This review can inform the design of interventions to improve coping strategies and mental health outcomes in people with cancer.