The invention discloses an 
underwater robot for 
submarine pipeline 
cutting. The 
underwater robot is mainly used for 
cutting submarine badly broken 
petroleum pipelines and comprises an ROV (remotely-operated vehicle) body, two 
cutting mechanisms, supporting legs and a small auxiliary 
manipulator, the ROV body comprises a frame, a 
buoyancy block, a 
propeller, a seven-degree-of-freedom 
manipulator, a five-degree-of-freedom 
manipulator, an 
underwater illumination device, a camera shooting device and a hydraulic 
electric control device, the supporting legs are uniformly distributed on two sides of the 
submarine pipeline cutting 
robot, a center line of the supporting legs is coincided with that of the cutting mechanisms, so that the ROV body is supported, the small auxiliary manipulator is connected below the 
submarine pipeline cutting robot through bolts and positioned in middle of the cutting mechanisms, the cutting mechanisms are fixed in the rearward front of the bottom of the 
submarine pipeline cutting robot through bolts, the cutting mechanisms and a pipeline are positioned by a positioning 
hydraulic cylinder, and the broken pipelines are 
cut by controlling rotation of a water cutter mechanism. The 
underwater robot can be automatically operated in 
deep water areas or special environments.