Disclosed is a barcode reader, comprising: a scanner unit which scans a barcode by emitting laser beam and receiving reflection light thereof to obtain image data; a judgment unit which judges a portion of the image data corresponding to each end portion of a swing width of the laser beam as a data unstable range and judges a portion of the image data other than the data unstable range as a data stable range; and a decoding unit which sets a tolerance of error of the image data low against a threshold in the data unstable range, the threshold being used to judge data width of black bars and white spaces of the barcode, to decode the data unstable range, and sets the tolerance of error of the image data high against the threshold in the data stable range to decode the data stable range.