Starch from cormels of cocoyam (Xanthosoma sagittifolium), cultivar Ede ocha and cultivar Ede uhie were extracted and milled into starch of fine texture and were further subjected to acid and enzyme modification treatments. Proximate composition, functional and amylograph pasting properties of the starches were evaluated. The starch samples were also used in the production of cookies at 5%, 10%, 15%, 20% and 25% level of substitution with wheat flour. The cookies produced were subjected to proximate analysis and sensory evaluation. The result of the sensory evaluation showed that cookies prepared at 5% level of substitution were most acceptable. After eight weeks of storage in light polythene bags, the cookies prepared at 5% and 10% levels of substitution with wheat flour were found to be more acceptable by the panelists. Observations on the functional properties showed that the modified cocoyam starches exhibited higher bulk densities than the untreated starches. Native and modified starches with the high water absorption capacity and swelling index were produced from cultivar Ede uhie. There was no significant difference (P < 0.05) in the solubility of the starch samples.