A fault root cause analysis method, wherein the method comprises: obtaining a first alarm event set, wherein the first alarm event set comprises a plurality of alarm events; for a first alarm event in the first alarm event set, extracting a feature vector of the first alarm event, wherein a part of or all features of the feature vector are used to represent a first relationship, wherein the first relationship is a relationship between the first alarm event and another alarm event in the first alarm event set; and determining, based on the feature vector of the first alarm event, whether the first alarm event is a root cause alarm event; the feature vector comprises at least one of an alarm severity level, an alarm name, and an event type, and further comprises at least one of an association attribute, a third relationship, a fourth relationship and a fifth relationship, wherein the association attribute is used to represent a second relationship between the first alarm event and the another alarm event in the first alarm event set; wherein the second relationship is an association relationship, wherein the third relationship is a time sequence relationship, the fourth relationship is a quantity relationship, the fifth relationship is a resource relationship, the quantity relationship is used to represent a ratio of a total quantity of all alarm events comprising the first alarm event that are the same as the first alarm event and that are in the first alarm event set to a quantity of all alarm events in the first alarm event set, and the resource relationship is used to represent a propagation relationship between the first alarm event and the another alarm event in the first alarm event set. obtaining a first alarm event set, wherein the first alarm event set comprises a plurality of alarm events; for a first alarm event in the first alarm event set, extracting a feature vector of the first alarm event, wherein a part of or all features of the feature vector are used to represent a first relationship, wherein the first relationship is a relationship between the first alarm event and another alarm event in the first alarm event set; and determining, based on the feature vector of the first alarm event, whether the first alarm event is a root cause alarm event; the feature vector comprises at least one of an alarm severity level, an alarm name, and an event type, and further comprises at least one of an association attribute, a third relationship, a fourth relationship and a fifth relationship, wherein the association attribute is used to represent a second relationship between the first alarm event and the another alarm event in the first alarm event set; wherein the second relationship is an association relationship, wherein the third relationship is a time sequence relationship, the fourth relationship is a quantity relationship, the fifth relationship is a resource relationship, the quantity relationship is used to represent a ratio of a total quantity of all alarm events comprising the first alarm event that are the same as the first alarm event and that are in the first alarm event set to a quantity of all alarm events in the first alarm event set, and the resource relationship is used to represent a propagation relationship between the first alarm event and the another alarm event in the first alarm event set.