A coin processing device comprising: a feed belt that normally rotates in contact with an upper side of a coin to convey the coin to a conveyance passage extending from an inlet-side passage portion to an outlet-side passage portion; a conveyance motor that normally rotates the feed belt during the normal rotation; a detection unit that is configured to detect the coin passing through a position determined in advance in the conveyance passage; and a control unit that is configured to switch the conveyance motor from a first rotation state where the conveyance motor normally rotates at a first rotation speed to a second rotation state where the conveyance motor normally rotates at a second rotation speed slower than the first rotation speed, in response to detection of the coin to be stopped by the detection unit, and then rotates the conveyance motor, wherein a falling portion for causing the coin to fall from the outlet-side passage portion is provided on a downstream side of the outlet-side passage portion opposite to the inlet-side passage portion, and wherein the control unit is configured to perform stop control for stopping one coin to be stopped on the outlet-side passage portion that is on the downstream side with respect to the detection unit, by switching the conveyance motor from the first rotation state to the second rotation state in response to detection of the one coin to be stopped by the detection unit, and then stopping the conveyance motor in response to a change from a detection state where the detection unit detects the one coin to be stopped to a non-detection state where the detection unit does not detect the one coin to be stopped. a feed belt that normally rotates in contact with an upper side of a coin to convey the coin to a conveyance passage extending from an inlet-side passage portion to an outlet-side passage portion; a conveyance motor that normally rotates the feed belt during the normal rotation; a detection unit that is configured to detect the coin passing through a position determined in advance in the conveyance passage; and a control unit that is configured to switch the conveyance motor from a first rotation state where the conveyance motor normally rotates at a first rotation speed to a second rotation state where the conveyance motor normally rotates at a second rotation speed slower than the first rotation speed, in response to detection of the coin to be stopped by the detection unit, and then rotates the conveyance motor, wherein a falling portion for causing the coin to fall from the outlet-side passage portion is provided on a downstream side of the outlet-side passage portion opposite to the inlet-side passage portion, and wherein the control unit is configured to perform stop control for stopping one coin to be stopped on the outlet-side passage portion that is on the downstream side with respect to the detection unit, by switching the conveyance motor from the first rotation state to the second rotation state in response to detection of the one coin to be stopped by the detection unit, and then stopping the conveyance motor in response to a change from a detection state where the detection unit detects the one coin to be stopped to a non-detection state where the detection unit does not detect the one coin to be stopped.