Modern democratic nations advocate the protection of "Equality", but the meaning of the Principle is still abstract and uncertain. Therefore, it is somehow complicated to apply such a principle to solve the issues of human rights. This essay is to discuss the limits of "Equal Principle" by means of three parts which are human rights system, national power, and private society. On the other side, rational modification and limit should be emphasized, lest we should run into a predicament of protecting "Absolute Equality". During the developing process of "Equality," its meanings and contents change with the different ages and societies. Therefore, this research paper, firstly, discusses the basic meaning of "Equality". Today, national power inevitably intervenes the operating process of equality protection, but the most important problem is how to deal with and balance the relationship between "Equality Protection" and "National Power," including their limits, standards, etc so that human rights can be protected in a reasonable way, and that is what the second part of this paper focus on. The last part is to examine the issues about" Equal Principle" in Taiwan.