A printing system includes a printer in which particular information is set to designate the printer is a qualified printer, and a host device for transmitting print information created by a particular application to the printer. The particular application has an information adding unit that adds information to the print information. The printer has a decision unit that decides whether the information added to the print information matches the particular information stored in the printer, and a print processing unit that prints the print information only if this is the case. This arrangement enables qualified electronic form data to be printed only by a qualified printer, and a qualified printer to print only qualified electronic form data, without requiring significant modifications of existing printer programs or electronic form data specifications.