A conveyance control device executes: a control step of detecting entering to a merging point adjacent area set on adjacent to each merging point on the conveyance route; a detection step of detecting whether there is an obstacle around the carrying cart; a communication step of performing, when the entering to each merging point adjacent area is detected, local wireless communications with another carrying cart by using a common frequency band and a common identification code set to values different among merging points; and a merging point passing control step of starting the communication step when the other carrying cart is detected in the merging point adjacent area in the detection step, and causing passing of a merging point in accordance with a priority set to each entering passage to the merging point, after a handshake with the other carrying cart is successfully performed in the communication step.