PURPOSE: To perform high speed conveyance and to smooth rise and fall characteristics by engaging a pair of pallet hook arms with respective two pallets located in the waiting position and the machining position of a preceding process and separating the pallet hook arms from the two pallets, conveyed to a waiting position through running of a servo motor, by means of backward movement.

CONSTITUTION: A pair of pallet hook arms 11 and 12 are advanced and engaged with two pallets P1 and P2 located in a waiting position I and a machining position II of a preceding process through operation of a hook actuator, and by means of running of a servo motor SM, the pallets are conveyed to the machining position II and a waiting position III of a subsequent process. The two pallets P1 and P2 and a pair of the pallet hook arms 11 and 12 are separated away from each other through backward movement operation of the hook actuator. This constitution can provide a pallet conveying device which has high speed conveyance, being fundamental performance as the pallet conveying device, and a high speed conveying function to smooth rise and fall characteristics.