The moleonlar orbitals, energy levels and oharge distributions of CpaZr(H)Cl(Gp=cyclopentadienyl group) oompleg by the semi-empirical EHMO method have been calculated. The resalts are as follows:(1) The lowest unoccupied molecular orbitals(LUMO) are chiefly composed of 4d_x³-y³, 4d_x³ and 4d_yz of the central Zr.atom,The higheat occupied molecular orbitals(HOMO) are chiefly composed of the orbitals of two Cprings;(2) The charge distribution of this oompleg has been obtained. The central Zr atom is positively charged and the Cp rings, chlorine and hydrogen ligands are negatively charged;(3) The Zr-H bond length is close to the sum of the ionic radii of Zr⁴⁺ and H^-, but not to the sum of the covalent radii of Zr and H atoms. This indicates that the Zr-H bond may be of ionic character.