Abstract: Abstract: In the process of dough blending, the water addition and mixing time have important influences on the sensory quality, physical and chemical properties, and texture of food products. The optimum amount of water addition can significantly improve the structure and quality of flour food. If the water addition is too high, the dough will be too soft and difficult to form. If the water addition is too low, the protein in the gluten cannot fully contact with the water, and thereby to form relatively low gluten. Alternatively, if the mixing time is insufficient, the internal structure of dough sheets will be rough and uneven with many particles, where the surface of dough sheets can be easy to tear. If the mixing time is too long, the surface of dough sheets will be too wet and sticky, unfavorable to the shaping operation of dough sheets. The moisture content of dough is also closely related to the properties of flour protein after dough formation. Taking wheat dough sheets as the research objects, the effects of water addition on the texture and protein properties of dough sheets under different mixing time were invesigated. Texture analyzer was selected to characterize the sensory physical property and texture characteristics of dough sheets, particularly related to mechanical properties. Fourier transform infrared spectroscopy (FTIR) was used to collect the infrared absorption spectrum and radiation spectrum of dough sheets. The protein content in the dough sheets was obtained using the Gauss deconvolution and second-order derivative methods. High performance liquid chromatography (HPLC) was used to determine protein content. The results showed that the tensile force and hardness of dough sheets decreased, while the extensibility and viscosity increased with the increase of water addition. In moderate water addition, the water molecules could be fully immersed in gluten protein to generate the protein hydrate, and thereby to form a gluten network with mutual adhesion, indicating good extensibility, high viscosity, strong tensile resistance, and low hardness. In low water addition, the flour cannot fully absorb water, the gluten protein cannot fully hydrate, and thereby the formation of dough sheets was rough and hard, with the strong instant breaking force. In high water addition, the starch in flour dissociated from the gluten network, while the gluten protein and starch were in the state of water absorption saturation, where too many water molecules existed between protein-protein and protein-starch particles to weaken the intermolecular force, thereby to reduce the viscosity, toughness, and the tensile strength of dough sheets, leading to extremely low hardness and pull deformation. The water addition can significantly increase the whiteness (L *) and red green value (a *) in the color of dough sheets. The yellow blue value (b *) reached the maximum at the water addition of 45%, due to the light refraction and the action of polyphenol oxidase, indicating the strongest browning of dough sheets. The b* value of dough sheets decreased when the water addition reached 50%, where the browning slowed down due to the dilution of polyphenol oxidase. The content of sulfhydryl group, secondary structure and large molecular weight polymer protein in gluten protein were also affected by the amount of water added to gluten. The content of sulfhydryl group reached the minimum at the water addition of 40%, as well the lowest occurred in the content of large molecular weight polymer protein formed by disulfide bond. The reason was that water can promote the formation of hydrogen bond, and then maintain the content of β- sheet and α-helix, further to stabilize the conformation of protein. There was complex influence of mixing time on the texture and protein properties of dough sheets. The extensibility of the dough sheets was the better, the tensile force, hardness were moderate , viscosity and sulfhydryl content were the lowest, and the content of β - sheet was higher at mixing time of 15 min. In the mixing time of 15 min and the water addition of 40%, the dough sheets achieved the optimum, particularly on the formation of chemical bond and the transformation of stable secondary structure. When the mixing time was not enough, the weak hydrogen bond between protein molecules cannot extend the gluten network, and thereby to increase the content of random coil of disordered structure. When the mixing time was too long, the formed hydrogen bond broke again to destroy the molecular structure of protein, where β-sheet was converted into β-turn. The findings demonstrated that the optimum water addition and mixing time can improve the texture characteristics of dough sheets and the cross-linking of gluten protein. The application of appropriate water addition and mixing time in production can provide reference for the production parameters of flour products.