To provide an image reader capable of executing direct printing by a printer regulated so as to print an image through a personal computer and to provide an image printing system using it.

The interface card 15 of this image reader 100 is provided with an LSI chip 18 obtained by integrating an interface circuit. The card 15 has a port 19 provided on the chip 18, and the port 19 is connected to a color printer 50 by an IEEE1394 fast serial bus 20. Since the chip 18 stores a leading function of an SBP (serial bus protocol)-2, direct printing can be carried out by using a color printer 50 which is regulated so as to print an image through a personal computer and has an LSI chip 54 on which a subordinate function of the SBP-2 is stored.