A novel multi-core fiber comprehensive parameter test system based on quantitative phase microscopy method, Brace-Köhler compensator method and machine vision technology was introduced. In order to characterize the test capability of peoposed system, the refractive index distribution and geometric structure of a seven-core fiber from YOFC, and the internal stress distribution of a single-mode fiber from Corning were obtained by this system, respectively. According to the former research, the quantitative phase microscopy method using transverse measurement could avoid the performance damage caused by truncated optical fiber efficiently. The improved Brace-Köhler compensatormethod was used to optimize the acquisition to get the optical delay. Combined with the machine vision technology, the system realized multi-modules, high spatial resolution, fast and accurate fiber parameter measurement. After sample processing, program debugging and optimization, the experiment results show that the accuracy of relative refractive index differencein multicore fiber was about 5×10^-4 magnitude and the internal stress measurement resolution of single-mode fiber wasabout 0.5 MPa. The comparison with the technicalindicators of existing optical fiber products proves that the system has measurement accuracy, and the test results provide data support for the application of multi-core fibers in multiple fields such as transmission and sensing.