In this study, rice flour:corn starch blend (50:50) used in gluten-free cookie production was replaced with taro [Colocasia esculenta (L.) Schott] flour at 20%, 40% and 60% levels to improve new functional food formulation. Taro flour was used as raw taro flour and cooked taro flour (CTF). Cooking process was applied to reduce the anti-nutritional factors in taro. Possible adverse effects of taro flour on technological properties of cookies have been tried to be eliminated by the increasing ratio of shortening (40% and 50%). Cookie trials were conducted according to 2 × 2 × 4 factorial design. Increasing taro flour ratio in cookie significantly (p <.05) increased moisture, ash, protein and mineral contents, surface redness and cookie hardness, and decreased diameter, thickness and surface lightness. Technological quality of the gluten-free cookies improved with CTF addition and high shortening ratio (50%) in cookie formulation. Practical applications: Utilization of taro flour in various cereal products is suitable for celiac patients because it does not contain gluten. As a result of this study a gluten-free cookie with high nutritional value and delicious has been suggested to the functional food industry. Another contribution on practical application is to create alternative utilization area for taro.