It has been determined that family members and relationship partners of persons with gambling disorders face a variety of problems. Since their problems have not yet been summarized in the literature, we conducted a scoping review to address this issue, and focused on the studies of problems faced by family members and partners of those with gambling disorders and studies on the effects of gambling problems on family members and partners. We searched electronic databases (PsycINFO, PubMed, and MEDLINE) and the reference lists of included studies published up to February 15, 2021 and extracted 2,760 studies. These studies were examined for eligibility, and yielded 101 items that met our predefined criteria, all of which were reviewed. Overall, this review found that (1) the presence of gamblers in families was related to increased gambling or other addiction related behaviors among family members; (2) a variety of intra-family conflicts were likely to arise between gamblers and their families and partners; (3) the presence of gamblers in families increased the risk of violence and abuse for family members, partners, and gamblers themselves; and (4) gambling problems generated a variety of physical and mental health problems in gamblers’ families as well as among others in their proximity. In the future, it will be important to establish beneficial support and treatment methods by using the difficulties identified by this review as outcomes in the treatment of gamblers, along with their families and partners.