Abstract: Compared with pure wheat flour dough,the effects of 9 kinds of purple sweet potato on the quality characteristics of mixed wheat flour dough were studied by measuring the farinograph characteristic,gelatinization,rheology,and water distribution. The results showed that compared with pure wheat flour dough,the water absorption,stability time,weakening degree,tolerance index and gelatinization temperature of different varieties of purple sweet potato wheat flour dough increased,while the dough bandwidth,peak viscosity,lowest viscosity,final viscosity,decay value,and retrogradation value decreased. Storage modulus(G'),loss modulus(G″)and deep bound water showed an increasing trend,while loss tangent(tanδ=G″/G')showed a downward trend. The dough stability and water retention increased with the addition of purple sweet potato flour. There was a very significant difference in the particle size of different purple sweet potato flour(P<0.01). The correlation analysis and cluster analysis showed that the average particle size of purple sweet potato flour was positively correlated with water absorption(P<0.01)and negatively correlated with stable time(P<0.01). The purple potato wheat flour dough was divided into three types:Type I included 7 kinds of purple sweet potato wheat flour dough,such as E Zishu 12,Type Ⅱ,and Type Ⅲ were Xu Zishu 8 and Mian Zishu 9,respectively. It provides a theoretical basis for the production of special purple sweet potato flour varieties for purple sweet potato wheat flour dough.