Objectives: With the rapid aging of the population and the increased availability of gambling facilities over the past three decades, older adults may gamble more and may be increasingly at risk for problem gambling (PG) or pathological gambling disorder (PGD). To facilitate a better understanding of gambling behavior among older adults that will inform preventive strategies, this article systematically examined empirical studies on issues related to older adults' gambling. Method: This article reviewed 75 empirical studies including data on the distribution and determinants of PG and PGD and the outcomes of gambling. Results: This review used the broad term of "disordered gambling" as a means to explain a continuum of problems caused by PG and PGD The analyses covered seven topics concerning older adults' gambling behaviors: Participation rates for gambling, prevalence rates of disordered gambling, motivation for initially beginning to gamble, risk and protective factors for disordered gambling, and negative and positive health outcomes from gambling. Discussion: Based on research gaps identified in the review, this article proposes six recommendations for future studies focusing on well-being of older adults who gamble, research method issues, and taking into account older adults' inspirations and adjustment to the aging process in the 21st century.