The multi-component object has received broadly investigation and application, however, how to detect and measure the quantitative structural information accurately is still an urgent problem. Therewith, a multi-component model is constructed. Combined with X-ray phase contrast imaging (XPCI) and phase retrieval (PR), systematic analysis of effects of the density difference of each component on the image contrast and precision of PR are conducted by simulation and experiment. The results show that XPCI and PR can provide a new method for nondestructively quantitative study of multi-component objects with high resolution and accuracy, which will play an important role in material sciences and biomedical applications, especially in the multilayer inertial fusion capsule and vascular imaging.