To provide a defect inspection apparatus capable of accurately aligning images only on the basis of small regions in the images while lowering increases of burdens on users.

A complex region search part 134 stores the positions of small regions acquired by searching a correct pattern image and an image of the small regions as a pattern for alignment in an alignment pattern storage part 135. An aligning part 136 reads the image of the small regions stored as the pattern for alignment from the alignment pattern storage part 135 and aligns an image to be inspected with the correct pattern image on the basis of the amount of position deviations between the small regions of the image to be inspected and the correct pattern image. A defect detection part 137 detects defects to be inspected on the basis of comparison results between the correct pattern image stored in a correct pattern image storage part 132 and the image to be inspected which has been processed for alignment at the aligning part 136.