Abstract: In order to study the effects of corn particle size on mixed flour farinograph properties and steamed bread quality characteristics,ordinary corn were passed through different standard screen to process into four distinct particle sizes including as 40,60,80 and 100 mesh screens. Their physicochemical properties of corn flour such as color difference,water holding capacity and pasting properties were analyzed. Using mixing flour consists of corn flour and wheat flour with a weight ratio of 3 ∶ 7 as raw material, mixed flour farinograph properties and steamed bread quality were studied. The results showed that with decrease of particle sizes,water holding capacity increased and pasting temperature decreased. The decreasing of corn particle size which added into steamed bread dough systems, increased dough water absorption slowly, reduced development time and stabilization time and raised softening as measuring by farinograph. The steaming experiment showed that the specific volume reduced,hardness increased and sensory quality increased first and then decreased with the decreasing of corn particle size. Sensory quality scores the highest with 80 mesh screens.