Abstract: ICF target material areal density and its distribution can be measured by counting beta particles passing through the material. It is necessary to calibrate the areal density measuring device using a series of standard materials with known areal densities and the same components with the materials to be analyzed. For the density measurement of a kind of ICF target material the calibrating method is proposed. This calibrating method uses the approximate, materials with composition of the ICF target material as the standard material. The transmissivity of beta particles possessing different energy can be simulated and computed by Monte-Carlo method when they pass different materials. The corresponding error to the measuring result is also obtained. The error is only several percent using pap