Abstract A lattice-based Monte-Carlo method is applied to simulate the switching behavior of the 2D ferroelectric system with dipolar defects. Two types of dipolar defects are introduced into the lattice-based ferroelectric system. One type of dipolar defects is that the position of the dipole displaces away from the lattice site, the other is the irreversible dipole. It is shown that the introducing of dipolar defects will decrease the coercive field. The first type of the dipolar defects will cause two successive 90° rotations of the direction of the dipoles during the process of switching, while the switching behavior of the ferroelectric system with the second type of dipolar defects shows almost a single 180° flipping.