A method for automatically generating news event of a certain topic applied in an electronic device analyzes text of the news event by a topic model to obtain topics, a probability distribution of keywords in each topic is established, and a time interval distribution of the keywords in each topic is calculated. Keywords within a preset probability distribution range are selected to reduce the size of a word bag relating to the topic, and a time interval range of the reduced word bag of the topic is determined. A calculation of text similarities of the text in a database is made to obtain a news article corresponding to each topic according to the time interval range of the reduced word bag, and a title of the news article as a target topic of the text of the news event is determined.