A pattern drawing apparatus includes a first image-pickup device for reading an alignment mark and reading a first pattern image for detecting a positional shift, a second image-pickup device for reading the first pattern image and reading a second pattern image for detecting a positional shift drawn by an irradiation light beam from the optical head while carrying out a relative movement between the table and the optical head, and a positional shift detection unit for obtaining a first coordinate difference between a center of a visual field of the first image-pickup device and a center of the first pattern based on a read image by the first image-pickup device and obtaining a second coordinate difference between the center of the first pattern and a specific position of the second pattern based on a read image by the second image-pickup device.