The interface dipoles for (111) lattice-matched semiconductor hererojunctions are calcula-ted employing the tight binding interface-bond-polarity model. The calculated results are com-pared with that of (110) and (001) interfaces. The effects of the interface orientation and the interface composition on the interface dipoles are discussed. It is shown that the dependence of the interface dipoles on the interface orientation and the interface composition is very weak tor isovalent heterojunctions, therefore the corresponding band offsets are almost isotropic; the anion-mixed (111) interface has a negative dipole and the cation-mixed (111) interface has a po-sitive one for nonisovalent heterojunctions, their average equals to the dipole of the nonpolar (110) interface.