To provide a pin fixing mechanism capable of reliably executing the locking action of a columnar pin forming a supporting point of rotation of a turning member, and excellently executing the mounting work, and an elevating/lowering device using the same.

The pin fixing mechanism includes columnar pins 40-45 forming supporting points of rotation of a turning member, a bracket through which the columnar pins 40-45 are penetrated, and a stopper 60 for preventing the rotation of the columnar pins 40-45. Slit grooves 46 which are orthogonal to the axial direction and parallel to the diameter direction are formed in ends of the columnar pins 40-45. The stopper 60 includes an arc-shaped curved part 62 having the same curvature as that of outer circumferential surfaces of the columnar pins 40-45, and a straight part 63 in an intermediate part thereof. The stopper 60 is fixed to the bracket by one bolt 65 while the straight part 63 is fitted to the slit groove 46, and the arc-shaped curved part 62 is abutted on the outer circumferential surfaces of the columnar pins 40-45.