To provide an IC card insertion and pulling-out monitoring device for surely judging that an IC card is correctly mounted at a normal position.

When an IC card 102 is correctly inserted, a terminal contact 108 of the IC card 102 is connected with a connector 110 and power source current flows to the IC card 102. As the result, a voltage drop is generated in a resistor 105, and a comparator 107 detects the generation of a potential difference at each of input terminals and outputs the result to a microprocessor 109. The microprocessor 109 judges that the IC card 102 is correctly inserted based on the output from the comparator 107 and makes the IC card 2 start the reading or writing of the data.