Abstract: An experimental platform was designed, and the sensitivity coefficient between the fiber compression strain and the resistance calibrated. The calibrated fibers are made into single-filament and multi-filament composite material system compression test specimens. Under the compressive load conditions, the influence of fiber fracture of multi-filament composite material specimen on surrounding fibers was investigated, and the maximum deformation of the fiber at the fracture was measured accurately. On the above basis, numerical methods were adopted to simulate the damage process of the micro-buckling of fibers around the fracture caused by the stress distribution of the matrix.