To prevent a delay in the feed of ready-mixed concrete to the site of placement and the spill of the ready-mixed concrete from a hopper by properly supplying the ready-mixed concrete into the hopper.

The concrete pump vehicle 1 having a concrete pump 9 for feeding the ready-mixed concrete in the hopper 11 is provided with an operating condition detecting means for detecting the operating condition of the concrete pump 9, a required supply computing means for computing the required supply of the ready-mixed concrete into the hopper 11 to obtain an operation command, and a transmission means 32 for transmitting the operation command. A mixer vehicle control unit 61 having a drum control part for controlling the rotation of the drum 22 upon receiving the operation command from the transmitting means 32 to supply the ready-mixed concrete in the required amount of supply is attached to a mixer vehicle 2 which rotates the drum 22 to discharge the ready-mixed concrete from a discharge opening 23 into the hopper 11.