To quickly judge the read state in a two-dimensional bar code reader.

This two-dimensional bar code reader is provided with a reference image irradiation means 6 for irradiating the arrangement surface of a two-dimensional bar code to be a read object with a reference image 32 provided with a prescribed shape, a read means 1 for optically reading the reference image irradiated on the arrangement surface of the two-dimensional bar code and converting it into electric signals and a read state judgement means 8 for judging the read state of the two-dimensional bar code from the deformation amount to an original shape of the reference image read by the read means 1. By using the result for distortion correction in the image processing of the two-dimensional bar code, the processing is performed in a short time. Also, by using the result as the informing data of the fact that the two-dimensional bar code can not be read, a user quickly corrects the read state.