Derrick mast with adjustable height

The utility model discloses a derrick mast with adjustable height. The derrick mast comprises a cross beam, an upper stand column and a lower stand column, wherein one end part of the cross beam is provided with a square steel plate, the other end of the cross beam is provided with a hoisting ring, a flange plate capable of being in butt joint with the square steel plate is arranged at the top end of the upper stand column, a base steel plate is arranged at the bottom of the lower stand column, each of the upper stand column and the lower stand column is provided with a height adjusting hole, the upper stand column and the lower stand column are in butt joint and are locked together through a steel pin inserted in the height adjusting holes. The derrick mast adopted by the utility model is simple in shape and structure and convenient to assemble and disassemble in a construction field; therefore the problems of an overlong wooden independent derrick mast in aspects of transportation and storage can be solved.