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In this study, Fe-40wt% TiB 2 nanocomposite powders were fabricated by two different methods: (1) conventional powder metallurgical process by simple high-energy ball-milling of Fe and TiB 2 elemental powders (ex-situ method) and (2) high-energy ball-milling of the powder mixture of (FeB+TiH 2 ) followed by reaction synthesis at high temperature (in-situ method). The ex-situ powder was prepared by planetary ball-milling at 700 rpm for 2 h under an Ar-gas atmosphere. The in-situ powder was prepared under the same milling condition and heat-treated at 900 o C for 2 h under flowing argon gas in a tube furnace to form TiB 2 particulates through a reaction between FeB and Ti. Both Fe-TiB 2 composite powder compacts were sintered by a spark-plasma sintering (SPS) process. Sintering was performed at 1150℃ for the ex-situ powder compact and at 1080℃ for the in-situ powder for 10 minutes under 50 MPa of sintering pressure and 0.1 Pa vacuum for both processes. The heating rate was 50 o /min to reach the sintering temperature. Results from analysis of shrinkage and microstructural observation showed that the in-situ composite powder compacts had a homogeneous and fine microstructure compared to the ex-situ preparation, even though the sintered densities were almost the same (99.6 and 99.8% relative density, respectively).