A bill processing apparatus with a credit card reader is configured such that a credit card insert slot (9) for inserting a credit card (50) therein is formed in the upper surface of a front mask (5), a credit card guide chute (20) connected to the credit card insert slot (9) is formed in the front mask (5) so as to be connected to a bill guide chute (8), and the lower surface (8b) of this bill guide chute (8) is bent so as to be proximate to the lower surface (5c) of the front mask, and when the credit card (50) is inserted into the credit card insert slot (9), the credit card (50) enters the bill insert slot (8) by way of the credit card guide chute (20) and reaches the lower surface (8b) of the bill guide chute (8), whereby credit card data can be stably read inside a front mask without changing the size of a conventional standardized front mask.