Recognition technology of paper currency number was studied.For the different characters between horizontal number and vertical number,we used different algorithms of preprocessing,denosing,and segmentation etc.Then used a regional template matrix as features to recoginise the number.For some easily confused letters,we distinguished them by using the information in some special regionals.In practice,the recognition rate of horizontal number is up to 98%,the recognition rate of vertical number is up to 93%.