Abstract: A shock absorber for the pumping unit of an oil well, adapted to be placed between the walking beam and a string of sucker rods in the borehole. The shock absorber has a tubular body of steel (or an equivalent structural material) having a closed top and an open bottom. A circular top on the tubular body has a central opening through which the polished rod is adapted to pass; and a rod clamp is affixed to the polished rod--above the tubular body. A plurality of elastomeric discs, typically four or five, are positioned in a stack within the tubular body; and each disc has an external diameter which is slightly less than the internal diameter of the tubular body. The plurality of elastomeric discs rest on top of a rigid circular plate having an OD smaller than the ID of the tubular body; and the circular plate, in turn, rests on top of a rigid spool.