The reaction cross sections and rate constants for the Cl + H2 --> HCl + H reaction have been calculated by quasiclassical trajectory(QCT) method with symplectic integral on two new three-dimensional ab initio potential energy surfaces (PES), BW2 and mBW2. The reaction cross sections of these reactions increase with the H2 rotational quantum number j at a given collision energy and vibrational quantum number upsilon = 0. The effectivity of rotational energy on the reaction is compared with that of translational energy.