An image processing apparatus includes an identification unit configured to identify a large dot region, in which large dots consecutively exist, and a small dot region, in which small dots consecutively exist, in a read image obtained by reading an image on a sheet, a determination unit configured to determine whether a difference in degree of brightness between the large dot region and the small dot region identified by the identification unit is less than a threshold value, and a processing unit configured to disable printing using the read image if the determination unit determines that the difference is less than the threshold value, and to enable printing using the read image if the determination unit determines that the difference is equal to or greater than the threshold value.