The invention discloses an access control system and a method based on face recognition. The access control system comprises a first trigger module, a second trigger module, a first image processing module, a second image processing module and a facial feature comparing module, wherein a first image collecting module can collect a wholly-body image of personnel in a first trigger area; a second image collecting module can collect a face image of personnel in a second trigger area, process the whole-body image and correct parameters; compared with all prestored outline information, all prestored face images in a correcting area can be screened out, and the prestored face images are matched and fused with the collected face image; the facial feature comparing module can control an access control system to unlock according to a matching degree of the face image; meanwhile, the access control system can sense that personnel enter and exit through a sensing module, so that advertisements can be broadcasted and interrupted in real time; the access control system disclosed by the invention can quickly and accurately perform image recognition, so that access control system response time delay is reduced, advertisement exchange is accurately achieved, a work efficiency of the access control system is improved, and convenience is brought to property management.