The invention discloses a gun for launching a fishing net. The gun comprises a launching body and a gun body, wherein the launching body comprises a central body (1); 4-8 grooves are axially formed inthe outer side of a cylinder at the front end of the central body (1); sliding chutes (10) are formed in two sides of each groove; a flying claw (14) is arranged in each groove; a positioning ring (2) is arranged at the rear part of the central body (1); the diameter-reduced part of the rear end part of the positioning ring (2) is in contact with a corresponding component of the gun body; and thegun body comprises a gun barrel (19), a long groove (20), a safety plug (21), a firing device (22), a fishing line wheel (23), an energy storage spring (24), a gun handle (25), a trigger (26), an elastic clamp (27) and a handle (28). The gun for launching the fishing net is sufficient in energy, safe and stable; after the launching body is launched, all the flying claws (14) can be separated fromthe central body (1) and fly outwards; a silk screen (12) is opened; fishes in water at a near position and a far position are captured; and the fishing efficiency can be greatly improved.