In preparing straw pulp, the digester was heated by an electrical current through the graphite electrodes immersed in the cooking solution. When digestion takes place in the digester, partial electrolysis of NaCl is expected to improve delignification and brightness of the pulp. The resulting properties of the pulp prepared by passing alternating current only were compared with properties of the pulp prepared by passing an alternating current followed by a direct current. The results obtained at the latter conditions showed some improvement from the former method.