The invention discloses a word-segmentation-based search method for improving the precision of word-segmentation-based search; the method comprises: subjecting an original search term to word segmentation to obtain a maximum segmented word group and a minimum segmented word group; if there are first items, including all segmented words in the minimum segmented word group, in a database, classifying the first items, finding from all classes, a class having the largest amount of the first terms as a target class, searching under the target class in the database for a term including any segmented word in the minimum segmented word group as first target term output; if there is the first terms in the database, judging a center word of the original search term to search the database to obtain second target term output so that a user may gain expected information. The invention also discloses a device for implementing the above method.