When user specifies a desired minimum font size through a host computer 2, and issues a print instruction to a printer 3, a recommended N-up number operating section 37 of the printer 3 performs an arithmetic operation to obtain a maximum N-up number with which font size not larger than the desired minimum font size are not included. A printing section 35 of the printer 3 prints the obtained N-up number of sheets of original document images on one sheet of paper.