The effects of different size of wheat flour on the quality of steamed bread were studied. The wheat flour was selected into four particle size: 140-160 mesh, 160-180 mesh , 180-200 mesh and 200 mesh above. The basic physicochemical indexes and rheological properties of raw wheat flour and different particle size groups were analyzed. Steamed bread's physicochemical indexes, texture analyses, microstructure observations, and sensory evaluations of steamed bread by different particle size flour were analyzed. The results showed that the physicochemical properties and rheological characteristics of wheat flour had significant difference (p<0.05): damaged starch and ash content in wheat flour increased with the decrease of particle size; the crude protein and wet gluten content within 180-200 mesh were higher than others and its gluten index was also higher; the steamed bread dough made of 180-200 mesh wheat flour had the highest elasticity, and better water holding capacity. With the decrease of particle size, the whiteness of steamed bread increased gradually, and the differences of pH values and water contents had little effect on steamed bread quality. The steamed bread made of 180-200 mesh flour had the highest specific volume. Texture analysis showed that the elastic value of 180-200 mesh flour was the best, and its hardness and chewiness were moderate. Scanning electron microscopy observed that steamed bread made of 180-200 mesh flour had a better continuity of gluten network structure, but the network structures of raw flour and 200 mesh flour was slightly worse and contained a large number of holes and loose gluten structure. The sensory evaluation showed that no significant differences in the specific volume, flavor and taste of steamed bread of wheat flour with different particle size ranges. However, the sample of 180-200 mesh had the highest total score, and it had a homogeneous structure and excellent elasticity and flavor. The comprehensive results showed that wheat flour of 180-200 mesh was the most suitable for making steamed bread.