The invention provides a service quality reduction early-warning method based on warning information, which comprises: a corresponding relationship between fault warning information of each equipment and the service quality affected thereby is predefined; a network element produces the relevant warning information after the equipment fault occurs and sends the warning information to a management system via a management system interface; the management system receives the warning information from the network element and then judges whether the warning affects a certain service based on the corresponding relationship, if yes, the management system labels the affected service in the warning information to form an integral warning information; and further the management system stores the integral warning information in a databank, performs the analytical treatment of the integral warning information in the databank and informs the maintenance staff of the warning information that may affect some service in a certain manner.