A disposable lancing device (10, 100) including: a lancet (14) housed in a housing (12) and urged by a spring member (16) such that a puncture member (52) provided at a distal end of the lancet (14) is adapted to extend out from the housing (12) so as to carry out a puncturing operation a locking ring (72) disposed within the housing (12) such that the lancet (14) is allowed to displace in an extension direction through the locking ring (72) a locking protrusion (60) provided to the lancet (14) and adapted to be engaged by the locking ring (72) so as to hold the lancet (14) in a puncture-ready position located deep in the housing (12) with the spring member (16) being compressed and an operating member (20) adapted to carry out the puncturing operation by rotating the locking ring (72) so as to disengage the locking protrusion (60) from the locking ring (72) and displace the lancet (14) in the extension direction by means of the spring member (16).
