Abstract: Cracking occurred in the valve body of F53 duplex stainless steel in the forging process. The cracking reason was analyzed by macroscopic and microscopic examination. The results showed that the forging processing properties were reduced by the higher initial forging temperature, the brittle phase was increased by the lower final forging temperature, the forging stress was increased by a forging large deformation, then the forging cracking was inevitable in valve body.