The crystallization kinetics of poly(p-benzamide) (PBA)/H 2 SO 4 and PBA/Nylon 6/H 2 SO 4 from both the liquid crystalline state and isotropic state was investigated by the depolarized light intensity (DLI) technique and polarized light microscope (PLM). The isothermal process of the transitions in the anisotropic phase can be described by the Avrami equation. The values of the exponent n were obtained by fitting the experimental data. The introduction of Nylon 6 into PBA/H 2 SO 4 has a significant effect on the crystallization kinetics in both liquid crystalline state and isotropic state, however, through different mechanism.