The invention discloses a clamping and laser cutting device of a power engineering elbow. The clamping and laser cutting device comprises a base, a shell, a gear ring, a laser cutting head, a telescopic mechanism and a workpiece clamping mechanism, wherein axial through holes are formed in both side walls of the shell, the gear ring is movably connected with the shell by virtue of a sliding connecting mechanism, the telescopic mechanism is fixedly connected with the gear ring by virtue of a bracket, the laser cutting head is connected to the telescopic end of the telescopic mechanism, the gear ring is connected with a rotary driving mechanism by virtue of a driving gear engaged with the gear ring, and the rotary driving mechanism is fixedly connected with the base. According to the device, the laser cutting problems of the irregular shape of the elbow, an inclined notch and the like are solved, the high-quality and high-efficiency cutting of the elbow is realized, the precision of the notch is high, and the production efficiency can be greatly improved.