1. A character recognition apparatus which recognizes characters from a document original read as an image and corrects a character string of a character recognition result in a word unit with a space character as a separator, comprising: a circumscribed rectangle formation portion which forms a circumscribed rectangle for each recognized alphabet character string; a fixed-pitch font determination portion which determines whether or not a font of the character string is a fixed-pitch font based on a distance between center lines in a width direction of the circumscribed rectangles which are adjacent; a portion for determining an excess space character which determines, when it is determined as a fixed-pitch font, that the space character is an excess space character based on that a character width of a space character in the character string is narrower than a predetermined width; and a portion for deleting an excess space character which deletes the space character determined as the excess space character from the character string, wherein the predetermined width is determined based on a histogram of widths of space characters of the character string.