Polarization includes rich information of the reflection and scattering properties of the objects, which can effectively improve the detection capability. Previous studies on the polarization imaging of underwater objects mainly focused on the degree of the polarization, however, the capacities of Stokes components for imaging the underwater objects are poorly known. Based on the tank experiments, the influences of object depth, sediment concentration, object material and detection band on the polarization imaging detection are investigated. The results show that compared with the traditional imaging based on radiation intensity, the polarization imaging can obtain clearer image and better information of boundaries and textures of underwater objects, with the capacity of diminishing the impacts of the water absorption and scattering effects. Moreover, the detection capacity of polarization imaging with increasing object depth deceases more slowly than that of the traditional imaging based on radiation intensity, indicating that polarization imaging can detect deeper objects. The influence of sediment concentration on polarization imaging is more significant than that on the radiation intensity imaging, but the polarization imaging can still detect the edge contour of the target in the high concentration of sediment. The detection wavelength has some influence on the capacity of the polarization imaging, and the blue and green light wavelengths are the optimal bands for polarization imaging of the underwater objects.