PURPOSE: To realize the card type telephone set convenient for carrying while thin profile and light weight are devised by forming the telephone set with connection of plural cards able to be folded freely.

CONSTITUTION: A switch section 4 having a dial function is provided on a 1st card 2 and a sound recording hole 6 with a microphone built in therein is formed under the card 2. Moreover, a telephone set use logic circuit is built in the 1st card 2. When the telephone set is in use, a 2nd card 12 is folded at an obtuse angle with respect to the 1st card 2, after a 3rd card 22 is folded in an opposite direction so as to form an acute angle with respect to the 2nd card 12, a lock pin 34 provided to a free end of a 4th card 28 is engaged with a lock slot 20 formed to the 2nd card 12 to fix the 3rd card 22 and a 4th card 28 to a position where they are formed almost in a chevron shape.