To provide a map data correction method which is capable of correcting the map images of vector maps without conversion of aerial photographs to ortho-image data and reducing a cost required for the correction of the vector maps.

In correcting the vector area map A6 for one block of the vector map 20, the vector area map A6 before the correction is extracted from the vector maps 20 and is superposed on photographic maps 22 and 23. When the vector image in the vector area map A6 is matched with the image of the photographic maps 22 and 23, the images corresponding to vector unit maps A6a to A6y of the vector area map A6 are segmented from the photographic maps 22 and 23 and model images R01 to R25 for correction are formed. The model images R01 to R25 for correction area superposed on the respective vector unit maps A6a to A6y of the vector maps 20 to be corrected and the vector images of the respective vector unit maps A6a to A6y are corrected in accordance with the images of the model images R01 to R25 for correction.