The invention relates to a microblog-data-oriented flu epidemic surveillance analysis method which comprises the steps of obtaining a part of microblogs to be used as a training microblog set, marking each microblog in the training microblog set, obtaining a microblog text lexical item set of the training microblog set, obtaining a microblog text primitive feature lexical item set of the training microblog set, obtaining a feature lexical item dictionary, vectorizing features, training feature vectors to obtain an SVM classifier, obtaining the rest of the microblogs to be used as a testing microblog set, obtaining a microblog text lexical item set of the testing microblog set, obtaining a microblog text primitive feature lexical item set of the texting microblog set, vectorizing features, automatically classifying microblogs in the testing microblog set through the SVM classifier, and visualizing classification results to carry out flu epidemic surveillance analysis. The invention further relates to a microblog-data-oriented flu epidemic surveillance analysis system. The method and the system can help people to find the propagation tendency of flu, large-range propagation of flu is timely and effectively stopped, and influenza pandemic is prevented.