This invention relates to a metalized skutterudite thermoelectric material having improved long-term stability and a method of manufacturing the same, wherein the skutterudite thermoelectric material is metalized with a multilayer structure including a Ti layer for preventing the diffusion of the skutterudite thermoelectric material and a Fe—Ni layer for preventing an increase in the thickness of an intermetallic compound layer, whereby the performance of the skutterudite thermoelectric material does not deteriorate due to diffusion and formation of the intermetallic compound even upon long-term use, thus exhibiting improved stability of use, and moreover, the lifetime and stability of a thermoelectric power generation module using the skutterudite thermoelectric material can be increased, whereby the power generation efficiency of the thermoelectric power generation module can be increased in the long term.