Abstract: The aim of this study is life prediction of IN738 LC gas turbine blade via Larson- Miller parameter method and fulfillment of some systematic metallographic, creep and hardness tests. Various calculative methods of remaining life prediction have been considered and Larson-Miller parameter method is used in order to predict remaining life of ABB-130 gas turbine blade. By investigation of the metallographic images it was observed that the hardening phase (γ’) becomes bigger after passing of a long time and under high temperature (780 °C) and has been converted from cubic to almost spherical status. It results in a decrease in the strength of the matrix and degradation of alloy’s metallurgical properties and eventually generation of continuous carbides in the grain boundaries, bigness and joining of γ’ particles, grain boundary refining and generation of creep voids, all of which resulted in satisfactorily calculation of remaining life time.