To provide a printed-circuit board in which an electric circuit element for matching the impedance is built in the card slot and the space of the printed-circuit board can be utilized efficiently.

The printed-circuit board has a card slot 10 which receives a card 20 that has an electronic component and a signal input and output pin 22 for expanding various kinds of functions and in which a data communication pin 11a, a power supply pin 11b, and a grounding pin 11c to correspond with the signal input and output pin 22 are provided. An electric circuit element of which one side is connected to the data communication pin 11a and the other side is connected to either one of the power supply pin 11b and the grounding pin 11c for matching the impedance with the card 20 is built in the card slot 10.