The surface of titanium was mod&d by depositing coatings of metals of Group VIII, Ib and IVb and heat treatment at 700Β°C in a vacuum. The polarization behavior of the mod&d specimens were different from that of unmodified titanium, depending upon the nature and quantity of the deposited metals, thus indicating the altered nature of the surfacc layer. The initial hydrogen absorption rate by the modified specimens during cathodic polarization in 0.5 M HZSO, was measured and the results are discussed in relation to the hydrogen evolution reaction characteristic of the deposited metals, the surface layer composition, etc. Metals which inhibited the formation of the surface oxide layer of titanium increased the hydrogen absorption rate. The surfaoe coverage of atomic hydrogen is suggested to be the critical factor in determining the hydrogen absorption rate of titanium. Among the metals studied, Ni was the most significant in improving the hydrogen absorption rate of titanium, resulting in a current efficiency of 62 % for hydrogen absorption (2.8 times that of titanium). Pt and Pb had an inhibiting effect on hydrogen absorption, with half the efficiency of untreated titanium. The present results suggest the possibility of controlling the hydrogen absorption rate of titanium during cathodic polarization by surface modification techniques.