A parking guide system, including: a memory which stores camera parameter information and design reference information; a travelling detecting unit which measures travelling information; an image receiving unit which sequentially receives a first image taken before travelling and a second image taken after the travelling from a camera; a characteristic point extracting unit which extracts and matches characteristic points commonly included in the first and images; a homography calculating unit configured to calculate a first homography based on the camera parameter information, the design reference information, and the travelling information, and calculate a second homography that is a homography between the first image and the second image based on coordinates of the characteristic point; and an error calculating unit which calculates a third homography that is a homography for correcting an image according to a result of a comparison of the first homography and the second homography.