The invention discloses a microblog rumor recognition method based on LDA and random forest. The method includes: using a crawler method to collect microblog data from a microblog official platform, and performing manual annotating; calculating user credibility features and microblog influence features through text content data processing and z-score standardized microblog data; calculating perplexity through LDA optimized text content and theme distribution probability, LDA theme and optimized text content word distribution probability; further building microblog feature vector; taking the user credibility features, the microblog influence features, the LDA optimized text content and the theme distribution probability as input features of a random forest model to build a microblog rumor classifier. The method deeply digs microblog text semantic information and is high in rumor classifying accuracy.