Abstract: Based on the radiographic physics, the imaging formula with various physical quantities is presented for the basic layout of flash radiography with the anti-scatter grid camera. Before reducing the formula, the role of the anti-scatter grid camera is discussed through numerical simulation and theoretical analysis in limiting X-ray scatter and noise and blur, and the radiographic method with the anti-scatter grid camera is explored. It is shown that the anti-scatter grid camera is provided with high sensitive, little scatter and high resolution. Therefore, the formula of the transmission image with only the point spread function of X-ray source can be obtained through twice radiographing with/without the graded collimator and object.