PURPOSE: To provide the automatic correcting circuit for horizontal display position which automatically corrects the deviation of the horizontal position in hardware.

CONSTITUTION: A data control part 1-2 which controls the value of first picture signal data, a data selector 5 which synthesizes first picture data and another picture data in a frame memory by using a window position and width setting register which sets the display range of another picture data on the picture, a coordinate display position comparator 4-2 which uses a synthesized data acquisition register 4-1 for read of designated coordinate data out of synthesized picture data to decode data and compares the coordinate position or picture data in the frame memory and that of first picture data with each other, and a horizontal position adjusting part which changes the extent of delay of the horizontal synchronizing signal in the first picture signal by using a horizontal position correction register 3-2 which sets the correction value from the coordinate display position comparator 4-2 are provided.