The result of the research shows that the regulation on pregnant woman who gets married because of adultery, according to Law No. 1/1974, is not explicitly regulated, but it is implicitly regulated in Article 2, paragraph 1 which stated that a marriage is legitimate when it was done according to each the couple's religion and belief. In Article 53 of the Compilation of the Islamic Law, it is stated that 1) a woman who is pregnant without marriage can be married off with the man who has impregnated her, 2) the marriage can be carried out without waiting for the birth of the baby, and 3) the marriage will not be done over again after the baby is born. The baby is considered legitimate, according to Law No. 1/1974. According to the Compilation of the Islamic Law, the child who is born from adultery is legitimate when the prospect husband is the child's biological father. In Article 99, paragraph 1 of the Compilation of the Islamic Law and Article 42 of Law No. 1/1974, it is stated that a legitimate child is a child who is born from legitimate marriage, but he will be illegitimate when the husband of his mother is the man who has not impregnated his mother. The regulation on an illegitimate child is stipulated in Article 100 of the Compilation of the Islamic Law and Article 43 of Marriage Law No. 1/1974. The legal protection for a child who is born from adultery, according to Marriage Law No. 1/1974 and the Compilation of the Islamic law, is that the Recognition of the Child which can be done by his father after all requirements have been fulfilled, and the child is legally legitimate.