A pattern inspection method and apparatus in which a charged particle beam is irradiated onto a surface of a specimen on which a pattern is formed, plural sensors simultaneously detect secondary particles emanated from the surface of the specimen by the irradiation, signals outputted from each sensor of the plural sensors which simultaneously detect the secondary particles are added, an image of the surface of the specimen on which the pattern is obtained from the added signals, and the image is processed to detect a defect of the pattern.