Family law as one of the most important branches of law regulates family relations through legal norms, and marriage as a social institution in modern societies occupies a special place and enjoys special protection from the state. In matrimonial law, as a sub-branch of family law, an important definition of marriage is given and it reads that a marriage is a life union of a women and a man regulated by law. By entering into a marriage in front of competent authority or in front of a representative of a religious community where the formal declaration of will or in other words the consent of the spouses is of a particular importance, comes to creation of personal legal and property law effects of marriage. A spouse can inherit a deceased spouse based on the law or a valid will, and in most cases it is inherited exactly on the basis of the law that is, based on the hereditary lines, where the spouse enters the first line of succession. If it comes to a divorce or annulment of the marriage, the right of inheritance between spouses gets lost. In other words, according to the law, the spouse has the right to inherit only if at the time of death he was in a valid marriage with the testator or in other words he was in a married union.