The anisotropic optical and thermoelectric properties of In4Se3 and In4Te3 are studied by the first-principles calculation using the full-potential linearized augmented plane-wave method and the semiclassical Boltzmann theory.The optical properties show highly anisotropic in the energy range between 0.0 and 12.0 eV for In4Se3 and between 0.0 and 10.0 eV for In4Te3 while it is isotropic in the higher energy range for In4Se3.In contrast to S,the anisotropies of the electrical conductivities and power factors are great affected by the change of the temperature.Their anisotropies become larger along three directions with the growth of the temperature.S2δ/τ along the y direction is much higher than that along the x and z directions for In4Se3,which shows that the thermoelectric thin films with excellent performance can be obtained along the(010)surface.By studying the anisotropy of transport properties,we find that the transport properties of In4Se3 are better than that of In4Te3,which mainly comes from the small band gap of In4Se3.The anisotropy of S2 δ/τ for In4Se3 is larger than that for In4Te3,and the anisotropy of S2 δ/τ is mainly due to the anisotropy of δ/τ.