Abstract: The main subject of the present paper is to investigate damage accumulation process in notched composite laminates before final failure. The perietrant enhanced X-ray radiography and nonlinear finite element method are used to analyze the process of damage accumulation and the damage zone growth in notched [0/90] graphite/epoxy laminates.Emphasis is placed on analyzing the failure mechanism of the materials. The comparision between the numerical results and the experimental results is made. The present atudy shows that reasonable establishment of constitutive relation for the materials after damage accurs is very important for the damage prediction with numerical method in macroscopic regime. Under macroscopic regime, the damage growth in composite materials is represented by the redistribution of stress and atrain. The present model in accordance with the failure mode from the observation in the experiments failly represent the phenomenon of stress relaxation after damage occurs.