Consanguineous marriage is a global health problem with several health-related and social adverse outcomes. In this study we aimed to identify the prevalence and epidemiologic features of consanguineous marriage. This case-control study was carried out at the premarital advisory centers in Tabriz city in the North-West of Iran. The participants consisted of 1532 subjects (766 couples) with166 couples as the case group. The one year occurrence rate of consanguineous marriage was 13.80%. After adjustment for other variables, age at marriage for both women (OR=0.90, 95%CI=0.86-0.94) and men (OR=0.87, 95%CI=0.82-0.93), and level of knowledge for both women and men were significantly related to consanguineous marriage. Father’s profession, participant's level of income, and parent’s consanguinity were independent predictors of consanguineous marriage in men but not in women. The frequency of consanguineous is still high, so it seems necessary to design and implement special preventive interventions including multi-level educational programs in order to address the problem.