Kinetics of the phase transition from isotropic to liquid crystal state, which is by analogy termed as liquid crystallization, was reported for the poly(p-phenylene terephthalamide)/H 2 SO 4 system. Experimental results show that the effect of the temperature on the liquid crystallization process is marked while the polymer concentration within the experimental condition employed has a negligible influence. Some preliminary results also indicate that the liquid crystallization process is accelerated considerably after an external shearing is applied. Assuming that the liquid crystallization is a nucleation followed by the growth process, a theoretical approach was attempted in this work. The theory developed provides a reasonable interpretation of the liquid crystallization kinetics in the lyotropic liquid crystalline polymers.