A conveyance system comprising: a track; a plurality of conveyance vehicles traveling along the track and each conveying a conveyed object (90, 90A, 90B); and a controller configured or programmed to output a conveyance instruction for the conveyed object (90, 90A, 90B) to the plurality of conveyance vehicles, characterized in that when a first conveyed object (90A, 90B) placed on a downstream port, which is a place capable of accommodating the conveyed object (90, 90A, 90B) thereon, is in a state waiting for collection, and when another conveyed object different from the first conveyed object (90A, 90B) is not placed on an upstream port, which is on an upstream side of the downstream port in a travel direction of the conveyance vehicles and capable of accommodating the conveyed object (90, 90A, 90B) thereon, the controller is configured or programmed to: wait without outputting a conveyance instruction instructing collection of the first conveyed object (90A, 90B) until any of the conveyance vehicles conveying a second conveyed object (90C, 90D) to the upstream port has been recognized until a waiting time set in advance has elapsed since the first conveyed object (90A, 90B) changed to the state waiting for collection; and output the conveyance instruction instructing collection of the first conveyed object (90A, 90B) when the waiting time has elapsed since a point in time when the first conveyed object (90A, 90B) changed to the state waiting for collection. a track; a plurality of conveyance vehicles traveling along the track and each conveying a conveyed object (90, 90A, 90B); and a controller configured or programmed to output a conveyance instruction for the conveyed object (90, 90A, 90B) to the plurality of conveyance vehicles, characterized in that when a first conveyed object (90A, 90B) placed on a downstream port, which is a place capable of accommodating the conveyed object (90, 90A, 90B) thereon, is in a state waiting for collection, and when another conveyed object different from the first conveyed object (90A, 90B) is not placed on an upstream port, which is on an upstream side of the downstream port in a travel direction of the conveyance vehicles and capable of accommodating the conveyed object (90, 90A, 90B) thereon, the controller is configured or programmed to: wait without outputting a conveyance instruction instructing collection of the first conveyed object (90A, 90B) until any of the conveyance vehicles conveying a second conveyed object (90C, 90D) to the upstream port has been recognized until a waiting time set in advance has elapsed since the first conveyed object (90A, 90B) changed to the state waiting for collection; and output the conveyance instruction instructing collection of the first conveyed object (90A, 90B) when the waiting time has elapsed since a point in time when the first conveyed object (90A, 90B) changed to the state waiting for collection. wait without outputting a conveyance instruction instructing collection of the first conveyed object (90A, 90B) until any of the conveyance vehicles conveying a second conveyed object (90C, 90D) to the upstream port has been recognized until a waiting time set in advance has elapsed since the first conveyed object (90A, 90B) changed to the state waiting for collection; and output the conveyance instruction instructing collection of the first conveyed object (90A, 90B) when the waiting time has elapsed since a point in time when the first conveyed object (90A, 90B) changed to the state waiting for collection.