Department of Chemistry, Jadavpur University, Calcutta-700 032. Benzo-, salicyl-, cinnamo-, phenylacetyl hydroxamic acids and their N-substituted phenyl derivatives are found to form· yellow coloured complexes with titanium of varied compositions at different acid concentrations and In different solvent mediums. The complexes, formed with hydroxamic acids, are extractable into isoamyl alcohol, but not into chloroform ; whereas the complexes, formed with N-phenyl substituted hydroxamic acids, are extractable into both isoamyl alcohol and chloroform with lesser intensity in the former solvent. Spectrophotometric studies have shown the existence of complexes with high ligand to metal ratios at lower acidities in case of titanium hydroxamic acid complexes. Exact reverse trend was observed among titanium complexes of N-phenyl substituted hydroxamic acids except N-benzoyl phenyl hydroxylamine. Extended Yatsimirskii's, Leden's and Harvey-Manning's methods were applied to evaluate stepwise and overall formation constants, of different complexes. For some constants an electronic computer (1BM 1130) was deployed using FORTRAN Programming.