The invention relates to the field of microblog news credibility, in particular to a news authentication method and a news authentication system based on a microblog information source. The method comprises the following steps of extracting the new information source as an information source to be authenticated, and obtaining the user information of a user corresponding to the information source to be authenticated; obtaining the mutual fans proportion, authenticated fans proportion and fans-to-attention number proportion of the user, and obtaining the social relationship credibility value of the user according to the three proportions; obtaining the user activity and history microblog average influence of the user, and taking the product of the user activity and the history microblog average influence as the social behavior credibility value of the user; obtaining the evaluation public opinion index of a microblog, finding the comment microblogs of the microblog, obtaining the comment public opinion indexes of the comment microblogs, and taking the comment public opinion index of the microblog and the public opinion indexes of the comment microblogs as a social evaluation credibility value; carrying out linear weighing summation on the three credibility values to obtain a comprehensive credibility value.