A printing control system includes a transmission part configured to transmit data from an information terminal to an image processor; an analysis part configured to analyze the data received from the information terminal; a format determining part configured to determine the data format of the received data based on the analysis result of the analysis part; a conversion requesting part configured to, in response to the format determining part determining that the data format of the received data is convertible into print data printable in the image processor, transmit the received data to a data converter and request the data converter to convert the received data into the print data; and a printing control part configured to print the print data returned from the data converter in response to the request of the conversion requesting part.