The invention provides an extraction definition method based on an EMS (Enhanced Message Service) system for a relay protection device signal template. Definition methods with different requirements can be divided into operation monitoring definition and functional logic definition. The two definition methods are used for template extraction based on relay protection device signals. The operation monitoring definition comprises defining a relay protection device signal template extracted by a template into different types of action, alarm (generally abnormal/importantly abnormal), state deflection and the like according to operation monitoring requirements; the functional logic definition comprises carrying out modularized classification definition on the relay protection device signal template extracted by the template according to protection function logic and endowing practical functional logic definition. The extraction definition method has extremely high practical application value for online monitoring and analysis of a relay protection device, so that the operation monitoring level of the relay protection device can be effectively improved, and a complete model foundation is provided for protecting motion analysis in case of failures.