A print data processing device that is a device for processing print data transmitted from a host device, and electronically providing printouts according to user needs without making changes on the host device side and without wasting paper.The print data processing device includes: a data storage unit that receives and stores print data sent from a host device; an information acquisition unit that acquires requirement information indicating whether or not printing on print media is required; a data processing unit that, when the requirement information indicates printing on the print media is not required, converts the stored print data to print simulation data that does not cause execution of a printing process by a printer; a data output unit that outputs stored print data or print simulation data to the printer according to the requirement information; and a response unit that receives the response to the host device from the printer based on the output print data or print simulation data, and relays the response to the host device.