To provide a counterweight for a construction machine, which can be easily split or assembled, and which is suitable for an attachment structure having an attachment surface hooked on a back surface of the construction machine or suspended from the back surface.

A step-part-to-be-locked 6 of an outside weight 3 is hooked on a holding step part 5 of an inside weight 2, and a protrusion 7 for prevention of displacement is protruded into a recess 8 to fix the inside and outside weights 2 and 3. In addition, attachment surfaces 101a and 101b configuring an inner wall surface of a counterweight part 4 are formed in a recessed shape in accordance with a shape of a construction machine-side attachment position.