This paper investigated the micro mechanical behavior of quenched Ti-6Al-4V alloy, microindentation experiments were performed in a wide range of maximum loads: 200, 300, 500, 700, 1000, 1500, 2000, 3000, 3500 and 4900 mN, and loading speeds: 10, 40 and 103 mN/s. The results revealed that loading speed had little influence on measurement of hardness and Young's modulus. Microindentation hardness experiments showed strong indentation size effects. Indentation hardness as well as Young's modulus decreased with the increase of indentation load. The decrease of Young's modulus was due to the damage of materials. The analysis of plastic behavior revealed that quenching temperatures had little effect on strain hardening exponent n, but had significant influence on yield stress sigma(y). (C) 2011 Elsevier Inc. All rights reserved.