["Scandinavian Journal of Psychology, EarlyView. ", "\nABSTRACT\nConspiracy beliefs have long been a recurring feature of human society; however, when they target disadvantaged groups, such as the LGBTQ+ people, they represent a particularly harmful phenomenon with detrimental consequences. Despite the increasing interest in the phenomenon, research to date has often overlooked the influence of an individual social environment. Indeed, recent evidence highlighted that individuals who experience limited social integration might be more vulnerable to adopting a conspiratorial mentality. In this regard, social isolation may represent a possible trigger, fuelling epistemic uncertainty and existential anxiety, and enhancing susceptibility to anti‐LGBTQ+ conspiracy beliefs. Hence, the current study (N = 820) investigated whether individuals who experience heightened levels of perceived social isolation are more likely to report high levels of anti‐LGBTQ+ conspiracy beliefs endorsement via an enhanced conspiratorial mentality. Results were in line with our expectations, pointing out positive associations between perceived social isolation and conspiracy beliefs, both directly and indirectly, as a function of greater levels of conspiracy mentality. Therefore, an individual's social isolation may represent a promising approach to highlighting the factors that produce fertile ground for the endorsement of anti‐LGBTQ+ conspiracy beliefs and may represent a promising aspect for identifying potential pathways for intervention and prevention.\n"]