This work investigates a sample of [45] ₈ CFRP beam that was usedfabricated to and record the initialization and progress of the lateral damage of the sample inreal time,including matrix crack,delamination,yarn fracture,etc.The damage mode has a certain effect on the strength of the composite.Three types of impact energies,5J,15J and 20J are used in the impact test.Under the low-velocity impact response of the composite beam was studied,the purpose is to reveal the damage process of CFRP beam and understand the relationship between complex failure modes.A high-speed camera was used to record the initialization and progress of the lateral damage of the sample in real time,including matrix crack,delamination,yarn fracture etc. and the improved algorithm was used to obtain the front image of the sample damage.Compared with the test results,it was found that the crack damage perpendicular to the yarn direction was significantly more than that parallel to the yarn direction by the binary image.The force,contact load,time and other factors recorded during the test were used to characterize the damage of the CFRP beam sample under low-velocity impact.In addition,the damage progression of CFRP beam can be visualized by the data.