摘要： 《合同法》第52条第5项及其司法解释对于纠正“违法即无效”的错误认识曾起到了历史性作用。但现有的学说及现行立法在就违法合同效力的判定路径上却存在着方向性的偏差，于司法实践并不具有真正的指导意义：区分民法内的强制规范与民法外的强制规范而异其效力，在我国并不可行；通过语义分析尚难以发现强制规范之所在；而将违法之“法”简单缩限为“法律、行政法规”上的“效力性强制性规定”，并不妥当，亦难以操作，且于价值及逻辑层面多有疑问；此外，将违法与损害社会公共利益予以并列，在逻辑上也有不合。故应将违法合同的效力判定纳入《合同法》第52条第4项，通过规范目的的发现及利益的衡量来最终确定违法合同的命运。

关键词: 违法, 无效合同, 强制规范, 社会公共利益, 利益衡量

Abstract: The article 58 of General Principles of Civil Law in 1986 says that “juristic act in the following categories shall be null and void: (e) those that violate the law or the public interest.”The article 52 of Contract Law in1999 states that a contract is invalid if the contract violates a mandatory provision of any law or administrative reg-ulation. After the Interpretation I of the Supreme People’s Court of Several Issues concerning the Application of Contract Law in 1999, people’s courts shall base themselves on laws enaced by the National People’s Congressand its Standing Committee and/or administrative laws of the State Council when confirming the invalidity of acontract, and not on local regulations or administrative rules and regulations. According to the Article 14 of the Interpretation II of the Supreme People’s Court of Several Issues concerning the Application of the Contract Law in 2009，the term “mandatory provisions” as stipulated in 52 (5) of Contract Law in 1999 shall refer to mandato-ry provisions on validity. Compared with General Principles of Civil Law, Contract Law and the above two Inter-pretations limit the scope of nullity for the freedom of contract. But the requirements in Contract Law and the above two Interpretations are still unreasonable. In fact, the specific provisions in Article 52 of Contract Law are not beneficial to judicial practice. Fundamentally speaking, the reason why contract shall be null and void is it’s damage to public interests or public policy. So we should come back to the key problem that the contract is in-valid if it is injurious to the public interests or public policy.

Key words: Illegality, Invalid Contract, Mandatory Rules, Public Interests, Balance of Benefits