To provide a transaction information transmitting system by which manpower is saved in the both of a customer (depositor) and an information provider (bank) and also various kinds of transaction information by customer such as balance and transfer contents in a bank account is quickly and surely provided to the customer.

The system is provided with a voice response part 8 receiving a transaction information providing request from the customer by voice with a communication line, an electronic mail transmitting part 7 capable of transmitting an electronic mail to a customer terminal 4 provided with an electronic mail receiving function, a customer data storage part 6 storing various kinds of transaction information by customer and a data transfer control part 9 controlling data reading from the customer data storage part 6 to the electronic mail transmitting part 7. The data transfer control part 9 transfers data D by customer related to an event in the various kinds of transaction information by customer from the customer data storage part to the electronic mail transmitting part 7 whenever the prescribed event occurs and the electronic mail transmitting part 7 transmits the data D by customer to the customer terminal 4 of the customer as the electronic mail.