It is an object to provide a bill handling device, the control of the entire device of which is simplified. The bill handling device comprises: a bill validator including a bill sensor for discriminating the validity of a bill inserted into a bill insertion slot and further including a bill conveyor for conveying the bill to a predetermined position and sending the bill, which has been discriminated to be invalid by the bill sensor, back to the bill insertion slot; and a bill accommodating unit including a bill accommodating section for accommodating a bill, further including a bill detector for detecting the bill which has been sent out, furthermore including a conveyance roller for conveying the bill to the bill accommodating section side independently from the bill conveyor by a conveyance force weaker than the conveyance force of conveying the bill by the bill conveyor while the bill detector is detecting the bill.