This paper mainly introduces the watertightness test of OVM250 cable system products. By comparing the watertightness test requirements of the three major international cable standards PTI2007, fib2005 and CIP2002, combined with the actual working conditions of the steel cable stays, fib2005 and CIP200 are considered 2 The two codes require the watertightness test of cable products, and the various test parameters are the highest requirements in the two codes. The test water pressure parameters are 3m water pressure as required by fib2005, the test device is installed at a tilt of 30 degrees and the test period is 6 weeks according to CIP2002 specifications. Due to the lack of corresponding test equipment in qualified laboratories at home and abroad,OVM company designed and processed the test equipment and supporting test equipment according to the determined test parameters and CIP2002 standard test installation requirements. Under the double witness of the National Construction Engineering Quality Supervision and Inspection Center and the United States CTL laboratory, the watertightness test was carried out successfully, and the watertightness test was sufficient The sealing reliability of OVM250 cable anchor is verified.