Soy protein isolate (SPI), soy protein hydrolyzate (SPH), and texturized soy protein (TSP) were used to fortify flour nutrition, and the rheological properties of dough and qualities of noodles were determined. Soy proteins increased the peak viscosity of flour paste. Dough fortified with TSP also exhibited more solid-like behavior with the highest storage modulus, while dough fortified with SPH showed the lowest storage modulus. Soy proteins increased the cooking loss of noodles. The protein loss of SPH-W noodles was up to 32.0%, much higher than wheat noodles, 13.3%, while the protein loss of TSP-W noodles was only 14.3%. Three types of soy proteins weakened the gluten network on different levels. The larger protein molecules in TSP linked with glutenin and formed the higher molecular polymers, counterbalancing the weakening effects deriving from the interfering with the glutenin-glutenin linkages. Therefore, TSP is more suitable to utilize in noodles.