The invention discloses a purchase demand evaluation system and evaluation method based on semantic recognition. The evaluation system comprises a data management module and an evaluation module, thedata management module is used for obtaining purchase demand information in a mail purchase demand document and updating a purchase information management standing book. The evaluation module is usedfor generating a purchase demand evaluation report according to the purchase demand information and historical purchase; therefore, integration of data acquisition, information analysis, data notification, demand evaluation, result notification, data sharing and the like of purchase demands is realized; according to the invention, automatic management and evaluation of massive purchasing demand data can be realized, the auditing efficiency of purchase demands is improved, the purchasing period is shortened, and resource waste or bargaining loss caused by repeated purchasing of technical development and insufficient supplier research is avoided.