The tight-binding method is used to determine the band structure and the character of the electronic states of biaxially strained CdTe-ZnTe (001) superlattices. The influence of the offset value upon the valence bands is studied. The nature and the value of the energy gap as a function of layer thicknesses is calculated. As the tight-binding model gives a full description of the electronic states, band mixing is correctly produced and we have shown how the heavy and light holes are strongly mixed near the band edges which may modify the optical properties associated with such states.