Method and system for linking entities

The invention discloses a method and a system for linking entities. The method comprises: pre-processing input texts and a knowledge base, obtaining mentions and contexts thereof, and entity keywords; retrieving candidate entities of each mention; classifying the mentions in two kinds according to the number of candidate entities of the mentions, the mentions whose number of candidate entities is smaller than a preset threshold being clear-cut mentions, and others being undefined mentions; performing first stage entity linking on the clear-cut mentions; through similarity of the mentions and the entities in the knowledge base, and similarity among the entities, using a method of a corresponding relation graph of a preset mention and the entities to complete screening of the candidate entities; and according to linked target entities, performing second stage linking on the undefined mentions. The method respectively performs calculation of entity linking in stages according to whether the mentions are the clear-cut mentions or not, so that complexity of the algorithm is greatly reduced. Through upgrading the contexts of the mentions, for example, the linked entities, entity linking can be performed on the mentions in a text more accurately and rapidly.