The surface morphology InGaAs layers with In composition of 0.3 on GaAs (001) substrates are simulated by the phase field method. We investigate the influence of the strain field induced by static point defects on surface morphology of the InGaAs thin film. Our simulation demonstrates that the rms roughness of the thin film surface is strongly dependent on the density and magnitude of the randomly distributed point defects. Point defects near the thin film surface can produce a relatively large change of the surface morphology. The influences of thin film thickness on the surface morphology with different defect distributions are illustrated in the simulations. Additionally, a combination of experiment and theory is used to examine the influence of the defect density and magnitude on the surface morphology and roughness.