Infidelity in romantic relationships is defined as a sexual and/or emotional act with a person outside of the primary relationship that destroys trust and stability in the relationship. In this research, the tendency to commit infidelity is defined through sexual behaviors, which is measured by the Intentions Towards Infidelity Scale which examines the likelihood that a person will remain faithful to their romantic partner in a current or hypothetical relationship. The aim of this research was to examine the role of individual characteristics (sociosexual orientation, emotional intelligence, personality traits), sociodemographi characteristics (gender, age) and contextual factors (relationship satisfaction, length of relationship, previous cheating on a partner) in the tendency to commit infidelity in romantic relationships. 435 participants between the ages of 18 and 57 took part in the research, of which 192 were men (44.1%) and 293 were women (55.9%). The results indicate that gender and age are related to the tendency to commit infidelity, that is, men and older people are more prone to be unfaithful than women and younger people. As for individual characteristics, sociosexual orientation, and the personality traits of conscientiousness, agreeableness and openness to experience proved to be correlates of intention towards infidelity. Extraversion, neuroticism and emotional intelligence are not related to intentions towards infidelity. Finally, the contextual factors that include relationship satisfaction and previous partner cheating are significantly related to intention towards infidelity, while the length of the relationship is not. Regression analysis revealed that sociodemographic variables explain 4.5%, personal characteristics 23.4 % and contextual factors 11.1 % of the variance in tendency to commit infidelity. The final percentage of the explained variance of the criteria is 39%, and nonrestrictive sociosexuality, low agreeableness and cheating in previous relationships were shown as significant positive predictors of the tendency to commit infidelity.