Adsorption of a water molecule on the surface of neutral and charged titanium, Tin0, ±1 H2O, n ≤ 9, clusters was studied in this work using density functional theory, BPW91-D2, all-electron calculations. Water adsorption is crucial for understanding the nascent solvation of Tin and H-O bond activation. Computed Tin0,±1 ground states, GS, allow a characterization of the structural, electronic, and energetic properties. Compact forms appear for the Tin0,±1, n ≤ 9 GS, and the estimated ionization energies (IE), electron affinities (EA) and binding energies (D0) follow the trends of available experimental results. The most stable clusters are Ti4+1, Ti50, -1, Ti70, ±1, and Ti90, ± 1, being in accord with the measured D0 for the cations. Overall, the cations show larger D0 that neutral and anions: D0(Tin+) > D0 (Tin) > D0(Tin-). Further, the IE are reduced by water adsorption on the Tin clusters, this being due to delocalization effects, through the network of the Ti–Ti and Ti–O bonds, of the most external valence electrons of Tin-H2O. For Tin+H2O, the lowest D0 occur at n = 4, 7, and 9, with maximums at n = 5 and 8, the highest D0 is for n = 1; being different from those of bare Tin+. Metal-oxygen Ti-O bond and Ti-H bond interactions account for the adsorption of water on Tin0,±1, which occurs on a metal atom of a triangular Ti3 face. In the Ti-O and Ti-H bond pattern, the metal atom is roughly placed in between the O and H atoms, originating agostic bonds, which produce H-O bond activation, being larger in the Tin––H2O anions. Thus, the titanium clusters may show catalytic behavior in their interaction with water molecules.