Objective Effectiveness of cancer control partly depends upon early identification and treatment. Men appear to be more likely to delay help-seeking for symptoms, resulting in later diagnosis. This review aims to provide a mixed research synthesis of the psychosocial barriers to and facilitators of help-seeking for cancer symptoms among men. Methods Systematic methods were followed, including a predefined research question and search strategy. Searches retrieved 7131 international records from online databases: MEDLINE (n=3011), PubMed (n=471), SCOPUS (n=896), Informit (n=131), PsychINFO (n=347), and Web of Science (n=2275). Forty studies were eligible for inclusion in the review (25 qualitative studies, 11 quantitative studies, and 4 mixed-method studies). Results There was strong observational evidence for several psychosocial barriers to men's help-seeking behaviour: low cancer knowledge and inaccurate symptom interpretation, embarrassment and fear, and conformity to masculine gender role norms. The strongest facilitating factor associated with men's help-seeking behaviour was encouragement and support of spouses and family members. The majority of research was qualitative and used small samples, making generalisations to the wider population difficult. Conclusions Men's help-seeking for cancer symptoms is influenced by several psychosocial factors, which, in part, may be gender-specific. Health promotion initiatives to improve help-seeking behaviour among men should aim to increase cancer knowledge, reduce embarrassment and fear, address social norms deterring timely help-seeking, and acknowledge informal help-seeking with spouses and family members. Increasing the theoretical grounding of research could aid cohesion across the research area and the design of effective health promotion interventions.