PURPOSE: To provide a coin detection device which can surely detect the passage of coin by providing a gate part formed by surrounding a part of the periphery of a guide part and plural optical sensors arranged for the whole periphery of the internal side of the gate part.

CONSTITUTION: An opening 6b which faces a coin pay-out port at the bottom of a coin mechanism 2 and which is formed in an extent so that it receives coin dropping from the coin pay-out port is provided for the upper surface of a guide route 6 being the guide part of coin. The gate part 8 where coin passes through is provided at the lower part of the guide route 6. The plural optical sensors X1-X4 and Y1-Y4 are arranged for the whole periphery of the internal side of the gate part 8. In the gate part 8, light of one or plural optical sensors X1-X4 and Y1-Y4 is interrupted in an optical sensor group even if the posture of coin 7 at the time of passage is any type. Thus, a part of a regular signal is inputted to a controller. Thus, the controller judges that coin 7 is passed.