PURPOSE: To omit the useless operations and to smoothly perform the transactions with an automatic transaction device by transmitting the read data to a center before input of the transaction data to confirm the possibility of transaction and then discontinuing the transaction when it is impossible.

CONSTITUTION: When a card is inserted, a CPU 21 sends the card together with the data read out of the card to a host computer 31 via a communication processing part 30. The computer 31 decides the validity of the corresponding account, the card and the balance respectively based on the account number and returns the valid or invalid result of the account to a terminal. Thus, the terminal decides whether the account is valid or not through the CPU 21. If not valid, the account NG is set to inhibit the transaction. Meanwhile, the CPU 21 judges whether the account NG is received or not when the input of a password number is not completed after the input of this number is permitted. If the reception of the account HG is confirmed, an input procedure is inhibited and the invalidity of the account is displayed. At the same time, the incapability of transaction is also displayed.