PURPOSE: To certainly read the content described on an account slip without an omission of reading by a method wherein the case characters filled in letter entry columns have been printed in auxiliary entry columns, marks are put at the positions of the characters in the auxiliary entry columns.

CONSTITUTION: When marks are detected by a mark detector 23, the mark detector 23 starts a mark position recognizing device 25 which takes out an image data from an input buffer 22 and detects the positions of marks put in first and second auxiliary entry columns 13 and 14 of an OCR account slip 11. According to the positions of the marks, a mark/character converter 26 searches a conversion table memory 27 and converts the marks to character codes corresponding to the positions of the character. Therefore, the character codes of names of a bank and a branch office corresponding to the positions of the marks put in the first and second auxiliary columns 13 and 14 of the account slip 11 are given to a transmitter 28. Then, the mark detector 23 starts a character recognizing device 24 which converts the image data except payee's names filled in the character entry columns 12 to character codes and sends them to the transmitter 28.