Type IIP supernovae (SNe IIP) are the most common class of core-collapse SNe. They often show rapid increase of polarization degree just after entering into the nebula phase following the luminosity drop. It is generally believed that this time evolution of the polarization originates from the emergence of the inner aspherical core (the aspherical core model), while an effect of polarized-scattered echoes by circumstellar (CS) dust around the SNe may also substantially contribute to this polarization feature (the dust scattering model). In this study, we examined the effects of the scattered echoes on the SN polarization through radiation transfer simulations, including various kinds of geometry and various amounts of CS dust. We found that asymmetrically-distributed CS dust, which is generally inferred for red supergiants, could indeed reproduce the observed polarization features. We also found that the wavelength dependence of the polarization in the dust scattering model is different from what is expected from the aspherical core model, which could be used to reveal the origin of SNe IIP through multi-band polarimetric observations.