To provide an automatic transport system where the transport time of an object to be transported is shortened.

A carrier controller 2 gives the instruction of a transfer device 8. Thus, the instruction of a transport controller 1 is simplified and the carrier controller 2 gives a transport instruction to the transfer device 8 before a carrier stops. Thus, the transport waiting time of the object to be transported is shortened. at the time of loading/unloading the object to be transported on/from the carrier 3 by the transfer device 8, the carrier 3 directly communicates with the transfer device 8 and the optimum timing of transfer is informed.