Identification of age in clinical forensic medicine is of great importance, especially when official papers are lacking. Determination of age is very important during application of certain laws otherwise injustice may harm somebody. When the forensic expert is asked to estimate age of somebody, he will depend on the developmental changes seen in his teeth, bones as well as puberty signs. To help our colleagues, authors described, in this article, different age groups in relation to the Egyptian Laws. The legislator was mindful about age groups in drafting the articles of the Constitution and the various branches of law. The present article highlights the impact of the legislator's view of age groups according to different branches of law, or more precisely, the rights and duties of each age. Description of laws and their articles in relation to different age groups is divided into two main axes; the Public law and the Private Law. Age groups in the Public Law including the constitutional, administrative, criminal laws are discussed in details. In addition, different age groups in relation to The Private Law including civil, labor, will, evidence and commercial laws are explained. Moreover, relation of age groups to laws regulating certain litigation situations and procedures in matters of personal status are discussed. From this short description, it can be concluded that the Egyptian legislator, like other legislators, paid attention when determining rights and obligations to take into consideration age differences between individuals, and his philosophy emerged that he divided the age stages into three stages: the stage of disqualification, the stage of lack of eligibility, and the stage of completion of eligibility.