Recently,thermal rectifier with inhomogeneous thermal conductivity has been theoretically proposed and experimentally observed.We theoretically investigate the enhancement of thermoelectric cooling performance in thermoelectric devices with spatial-dependent inhomogeneous thermal conductivity.We find that the dissipation of Joule heat in such thermoelectric devices is anisotropic which differs from that in thermoelectric devices with homogeneous thermal conductivity.The anisotropic dissipation of Joule heat could enhance the heat absorption at the heat source,which leads to an significant enhancement of the maximum cooling power and the maximum cooling temperature differential.The expressions of the thermoelectric figure of merit(ZT)and the coefficient-of-performance(COP)are modified by the introduction of an inhomogeneity factor which describes the anisotropic dissipation of Joule heat.Our finding shows the potential application of thermal rectification effect on searching for thermoelectric refrigerator with high performance.