Abstract: This study based on the technology evolution theory, S-curve and bibliometrics, verified product evolution was accompanied by the evolution and transition of a number of sub technologies. It judged MRI was in the stage of underdevelopment and a new round of technology was being developed. It was found that the value of MRI equipment in scientific research or clinical application in foreign countries was higher than that in China by comparing the literatures at home and abroad. And there was a gap between China and the world scientific center in the independent R&D capability. The study verified the applicability of the technical evolution theory and the evaluation empirical laws in the medical devices evaluation, and explored the operability of the assessment tools. This paper not only provided a reference for equipment configuration, but also showed the gaps of key technologies in home and abroad and provided a reference for upgrading China's independent innovation and industrial technology.