To provide an automatic accounting device surely operable with a simple structure.

This device comprises a commodity insert port 21, a commodity discharge side part 2x, a commodity guide 22 supporting a commodity from a lower side so as to slide the commodity from the insert port to the discharge side part by the gravity; a shutter 23 opening and closing on the commodity guide 22 to stop the commodity in the middle; and a reader 25 detecting commodity information in the stationary state. A sensor detecting the passing of the commodity is provided in the vicinity of the opening and closing part of the shutter 23, and the commodity guide 22 is inclined.