The response of different concentrations of α-amylase and ascorbic acid on rheological characteristics of weak wheat flour was studied by the three dimension polynomial quaternary model. Flour physicochemical characteristics, dough extensogram, bread texture profile analysis and sensory properties of pan bread were determined. All-purpose flour was treated by fungal α-amylase and ascorbic acid compared with strong flour which using for pan bread production, and then investigates differences of dough extensograms and pan bread quality characteristics. Predicting individual extensograph parameters (Y) was assumed by quadratic polynomial regression model for the independent variables (fungal α-amylase concentrations or ascorbic acid concentrations (X)) to optimize the extensograph parameters (Y) used regression analysis. Three-dimension contour plot was used as a method to study the response surface of different extensograph parameters (Y) as dependent variables with fungal α-amylase concentration and ascorbic acid concentration (X and Z) as independent variables. The obtained optimum predicting concentrations were verified, by using applied extensograph trials and then manufacturing pan bread. Using optimal predictive fungal α-amylase and ascorbic acid concentration levels give accepted extensogram parameters relationship r² values and good pan bread quality, fit to the strong flour characteristics.