In order to study the effect of the amount of oats on the quality of potato composite noodles, potato and wheat flour were used as main raw materials. Using texture analyzers, scanning electron microscopy and other technical means, supplemented by statistical methods such as principal component analysis and fuzzy mathematics, comprehensive examination of texture characteristics, microstructure, drying characteristics and sensory characteristics of composite noodles. The results showed that with the increase of the content of oat flour, the masticatory factor, viscoelastic factor and hardness factor of the main texture components decreased first and then increased. The structure density, porosity and effective moisture diffusion coefficient also showed a tendency of decreasing first and then increasing, and the drying characteristics of composite noodles became worse. When the content of oat flour was 10, it had the highest chewability, viscoelasticity and hardness, compact structure and large effective water diffusion coefficient, and the sensory evaluation (color, appearance, mouthfeel and palatability) of the composite noodle was the best.