This study was aimed to investigate the effects of acid treatment on the surfacee characteristics ofgrit-blasted titanium alloy (Ti6Al4V). These treatments included (a) Al2O3 blasting, (b) Al2O3 blasting + HF acid etching, (c) Al2O3 blasting + HCl/H2SO4 acid etching, and (d) Al2O3 blasting + HF acid etching + HCl/H2SO4 acid etching. The surface topography and chemical composition of the samples were identified by field-emission scanning electron microscopy and X-ray photoelectron spectroscopy, respectively. Roughness of the as-treated samples was obtained from atomic force microscopy (AFM) and profilometry. Wettability of the samples was measured using sessile drop method. The results showed that porous structure on the surface of titanium alloy was prepared by dual acid etching treatment and the surfaces treated with acid had higher roughness and better wettability than the surface treated only by grit-blasting.