Releasing tool

The invention relates to the technical field of oil development, and discloses a releasing tool, and a first assembly comprises an upper joint, a first connecting sleeve, a piston rod, a piston, a supporting claw and a limiting mandrel. The second assembly comprises a second connecting sleeve and a main body pipe, the second connecting sleeve is coaxially arranged outside the supporting claw at intervals, one end of the second connecting sleeve is connected with the first connecting sleeve in a sleeving mode, the other end of the second connecting sleeve is in forward threaded connection with the first spacer sleeve, and one end of the main body pipe extends into the second connecting sleeve and is in reverse threaded connection with the supporting claw; and the supporting claw can be separated from the main body pipe to realize hydraulic releasing. When the first assembly is rotated in the forward direction through the upper connector, the threaded connection between the supporting claw and the main body pip