An image forming system includes an information processing apparatus and an image forming apparatus. The information processing apparatus includes a conversion information forming unit for creating object specifying information and object conversion information; a conversion information combining unit for creating combined print data; and a transmission unit for transmitting the combined print data to the image forming apparatus. The image forming apparatus includes a reception unit for receiving the combined print data; an information obtaining unit for obtaining the object specifying information and the object conversion information; a conversion unit for converting the combined print data to create converted print data according to the object specifying information and the object conversion information thus obtained; and a printing unit for performing a printing operation according to the converted print data.