A circuit board transportation device for transporting a circuit board in a predetermined transport direction, comprising: a guide member (29a, 29b) that is provided in such a manner as to extend in the transport direction and has a guide surface that comes into abutment with a circuit board from the outside of the circuit board in a perpendicular direction that is a direction perpendicular to the transport direction; a conveyor belt (21a, 21b) that extends along the guide surface in the transport direction to support an end of the circuit board positioned in the perpendicular direction; a supporting member that supports the conveyor belt from below; and a drive unit (23a to 25a, 26a, 27) that moves the conveyor belt in the transport direction, wherein the conveyor belt (21a, 21b) has: a belt base portion that is located under the guide member and extends both ways of the perpendicular direction from the position of the guide surface; and a projection that extends upward along the guide surface from a position, in the belt base portion, closer to the circuit board than the guide surface in the perpendicular direction up to a position between upper and lower ends of the guide surface, characterised in that the conveyor belt supports the circuit board by means of the projection, wherein the projection is configured to come into abutment with the guide surface. a guide member (29a, 29b) that is provided in such a manner as to extend in the transport direction and has a guide surface that comes into abutment with a circuit board from the outside of the circuit board in a perpendicular direction that is a direction perpendicular to the transport direction; a conveyor belt (21a, 21b) that extends along the guide surface in the transport direction to support an end of the circuit board positioned in the perpendicular direction; a supporting member that supports the conveyor belt from below; and a drive unit (23a to 25a, 26a, 27) that moves the conveyor belt in the transport direction, wherein the conveyor belt (21a, 21b) has: a belt base portion that is located under the guide member and extends both ways of the perpendicular direction from the position of the guide surface; and a projection that extends upward along the guide surface from a position, in the belt base portion, closer to the circuit board than the guide surface in the perpendicular direction up to a position between upper and lower ends of the guide surface, characterised in that the conveyor belt supports the circuit board by means of the projection, wherein the projection is configured to come into abutment with the guide surface. a belt base portion that is located under the guide member and extends both ways of the perpendicular direction from the position of the guide surface; and a projection that extends upward along the guide surface from a position, in the belt base portion, closer to the circuit board than the guide surface in the perpendicular direction up to a position between upper and lower ends of the guide surface, characterised in that the conveyor belt supports the circuit board by means of the projection, wherein the projection is configured to come into abutment with the guide surface.