The study of concrete based on CT Images has been a heated issue in recent years. Normally the study focuses on 2-D meso--concrete image, but sutdy on the construction of 3-D meso-concrete are not paid much attention to which limits the scope of the research and intervene with the overall analysis of calculation on the forces in any circumstances. Owing to this point, The author offers a new tech-VTK system based on the ray-casting which also can achieve visualization. After tests, the new method is obviously more accurate and effective in guidance to build concrete material numerical model. In short, it is instructive and significant to solve the problems in this field.