Abstract: In light of the fact that the full-scale steel pipe collapse test has such advantages as stringent testing criteria, high operation cost, and long installation and working cycle, etc., a pipe-ring collapse testing system is designed to test the 3 500 m deep-water submarine linepipe during the trial production inspection.Elaborated in the paper are the main aspects of the said testing system, including the operating principle, the structure, the specimen-preparation method, the testing procedure, and calculation of the theoretic collapse limit value.And the system is actually used to perform pipe-ring collapse test.It is identified via the analysis that the testing system is in possession of such advantages as simplified configuration, scientific test procedure, and being capable of performing continuous ring-collapse limit value testing to steel tubes with high repeatability.It is also emphasized that the ovality and wall thickness tolerance are the sensitive factors which affect the collapse performance of the steel pipe.