Abstract: This article explains the relations between economic law and social law, and points out that both have many different aspects such as the subject of the benefit, the intrinsic characteristic, the external intervention, and so on. So, both are the two co-existing legal departments, but the two are not completely oppositve, and both are consistent with each other as against the ultimate objectives, such as the pursuit of essencial fairness, the safeguarding of basic human rights, the promotion of the sustainable development, and so on.