The present invention provides a position detection apparatus including a detection unit configured to detect moire caused by overlap between a first diffraction grating including patterns arrayed in a first direction and a second diffraction grating including patterns arrayed in the first direction, and a processing unit configured to obtain a relative position of the first diffraction grating and the second diffraction grating based on the moire, wherein a width of an end pattern of patterns included in at least one of the first diffraction grating and the second diffraction grating in the first direction is smaller than widths of remaining patterns of the at least one diffraction grating in the first direction.