The goal of this study was to test the relationship of sociodemographic variables, the Dark Triad, Five factor model and habits of using social networks with belief in conspiracy theories. We tested whether these variables had an incremental contribution to explaining the variance of the criterion, using three steps in hierarchical regression analysis. The first step included sociodemographic information, the second personality characheristics, and the third habits of using social media. The study was carried out on 219 participants, in the age range from 19 to 77 years (M = 40.2). The participants filled out an online questionnaire about their sociodemographic information and information about their social media habits, the BFI-10, the Short Dark Triad questionnaire and the Generic Conspiracist Belief Scale. The results showed that the first step explained a significant percentage of variance of the belief in conspiracies (6%), and that younger people and right-wing politically oriented had higher scores in belief in conspiracies. The second step did not explain an additional significant percentage of the criterion (7%), but Machiavellianism showed a significant independent contribution to explaining the variance of the criterion: participants high in Machiavellianism had higher scores on belief in conspiracies. The third step explained a significant additional percentage of the criterion variance (4%): participants who considered themselves addicted to social media showed higher scores of belief in conspiracies. In the third step, the total percentage of the explained criterion variance was 17%, and the significant predictors were Machiavellianism and addiction to social networks.