Abstract: In order to develop staple foods containing high content mashed potato, the optimal formula of potato steamed bread with 50% mashed potato was explored. The formula of potato steamed bread was optimized by single factors and orthogonal experiment with taking potato dough fermentation characteristics, sensory evaluation, texture and color difference of potato steamed bread as indicators. The results showed that with the increasing of gluten content, the specific volume of dough increased firstly and then decreased, but the width to height ratio decreased initially followed by an increase. The hardness, stickiness and chewiness of potato steamed bread decreased initially, and then increased, while the sensory score increased firstly and then decreased. As palm oil and yeast contents increased, the specific volume of potato dough increased, but the width to height ratio decreased. The hardness, stickiness, chewiness and sensory score of potato steamed bread increased gradually. The optimal formula was obtained as follows: Potato 50%, flour 32%, gluten 5%, water 7.0%, palm oil 4%, yeast 3.5%, baking soda 0.2%, salt 0.3%, in which the sensory score of steamed bread was 90.50 scores, and the potato steamed bread had smooth surface, bright and uniform color, upright and full appearance, and potato aroma. The study could be used as theoretical basis for potato staple food processing.