知情同意是医疗侵权法上的一个核心概念。本文在介绍了知情同意原则的体系功能之后,对披露义务的例外情形、替代同意的具体规则进行探讨,从边缘处研究知情同意原则的功能。最后,指出除了法定的替代同意之外,还应有约定的替代同意的规则,并由此强调在医疗关系当中引入约定机制的必要性和可能性。 Informed consent is a core concept in the medical tort law. After introducing the system functions of the principle of informed consent, this article explores the exceptions of disclosure obligations and the specific rules of alternative consent, and studies the function of the principle of informed consent from the periphery. Finally, it is pointed out that in addition to the statutory alternative consent, there should be agreed rules of alternative consent, and thus emphasize the necessity and possibility of introducing the agreed mechanism in the medical relationship.