An offline programming device for preparing an operation program for making a robot with a hand perform a handling operation for an object with respect to a machine tool. The device includes a hand-position designating section designating a relative positional relationship between the object and the hand when the hand holds the object; a first calculating section determining a position and orientation of the object mounted on the machine tool when the robot performs the handling operation, based on a command specifying a position of the object and included in a workpiece processing program given to the machine tool; a second calculating section determining a position and orientation of the robot acting to hold the object by the hand when the robot performs the handling operation, based onthe relative positional relationship between the object and the hand and the position and orientation of the object; and an operation-program generating section generating the operation program by using the position and orientation of the robot.