Sometimes the experience of women is an unpleasant combination of marginalization, violence and cultural domination. To ethically encounter with this situation, one approach is equality; however, its content is controversial due to its open source text. Equality is a descriptive concept, and normative; within the form of a descriptive concept, it refers to a descriptive relationship between two individuals who are similar in some respects. In the normative sense, that belongs to the world of credit and prescribes a particular behavior to all, it is related to our understanding of what should be and is based on desired value which is often "justice". In international law, among the three discourses of equality (capabilities, rights and human capital), the rights is recognized in the framework of the primary rules and through treaties, custom and judicial procedures, which are the formal sources of this legal system, but fails in the actual sources of international law and its secondary rules. This research, by descriptive-analytic approach, shows equality as a legal general principle; its forms, and its relation to the concepts such as discrimination, difference, agency, empowerment and investigates its position among the primary and secondary rules of international law.