The invention provides a judgment device for judging a bar code region comprising bar codes in a document page printed with document content and comprising at least one bar code. The judgment device comprises a conversion portion, which is used for carrying out conversion to obtain a binary page image; a pixel correction portion, which carries out correction to obtain a corrected page image; a scanning path setting portion, which is used for setting a scanning region and two scanning paths; a scan obtaining portion, which is used for locking the corresponding regions one by one, carrying out scanning and obtaining two change times; a first change comparison and judgment portion, which is used for carrying out comparison and judging whether the case that one of the two change times is larger than a time lower limit threshold value and the other is smaller than a time upper limit threshold value exists, and if so, a feature point setting portion sets the center point thereof as a feature point; a calculating and setting portion, which is used for carrying out calculation and setting a feature point region; and a feature comparison and judgment portion, which is used for carrying out comparison and judging the feature point region, and when the quantity and dimensions of the feature points surpass a preset quantity threshold value and a preset region dimension threshold value, a bar code region judgment portion judges the corresponding feature point region to be the bar code region.