An arrangement comprises a puncturing instrument including a cylindrical box, a plurality of puncturing needles held in an axially serially connected state, a locking member for locking the puncturing needle cartridge at an axial predetermined position, and an elastic urging member urging the puncturing needle cartridge in one direction, and a puncturing needle replacing jig which allows the setting of a puncturing position for the puncturing needle cartridge and the discarding of used puncturing needles, in order to enter into a subsequent puncturing action after the puncturing of the puncturing needle. Thus, it is an object to provide, in an instrument for puncturing the surface of a living body, a highly safe puncturing instrument set having a plurality of puncturing needles, capable of continuous puncturing action by a simple operation.