In this paper, we have studied the propagation of dust acoustic modulated waves in the polarized dusty plasmas. The distributions of electrons and ions are Boltzmann and Kappa, respectively. We have used the reductive perturbation method (RPM) to investigate in detail the nonlinear amplitude modulation of dust acoustic waves in an unmagnetized collisionless polarized dusty plasma and a modified nonlinear Schrodinger equation governing the evolution of the dust acoustic envelope waves has been derived. The effects of the Kappa parameter on the modulational instability (MI) was discussed by using the numerical values. It is found that increasing the value of 𝜅 causes to increase the value of the dispersion relation and the group velocity. It was shown that the MI maximum growth rate firstly increases and then decreases as the mentioned plasma parameter increases.
