The Bedouin population in Israel is a semi-nomadic traditional patriarchal society. Consanguineous marriages are very common, contributing to high rates of congenital malformations and genetic diseases, resulting in high infant mortality. Data on consanguineous marriages among Bedouins in Israel are limited. This study examined the current prevalence of consanguineous marriages and their determinants among Israeli Bedouins. One thousand two hundred ninety Bedouin women who delivered in the maternity wards of the only hospital serving the Bedouin population were interviewed between November 2009 and January 2010. The prevalence of consanguineous marriages was 44.8 %. The most common type of spousal relationship was first cousins (65.7 % of all consanguineous marriages). The mean inbreeding coefficient was 0.0238. Factors significantly associated with consanguinity were less years of schooling (OR 0.94, 95 % CI (0.88-0.99), p = 0.02) and younger age at marriage of the wife (OR 0.90, 95 % CI (0.80-0.96), p = 0.0002). In conclusion, the rate of consanguineous marriages among Bedouins is very high, making this population at risk for congenital malformations and genetic diseases. Efforts should be directed at better education and provision of premarital and prenatal counseling on the health consequences of consanguineous marriages and the possibilities to lower those risks.