Abstract: In the present study, reconstituted coarse cereals using oats, buckwheat and sorghum as the main raw materials were produced and the effects of key processing conditions（proportion of raw materials, maturing time,drying process） on the contents of protein, lipid, glucose and mineral elements including iron, zinc and manganese were further researched, and the key processing technologies were optimized employing response surface methodology on the basis of single factor experiments（sensory evaluation as the indicators）. Results showed that the optimum processing conditions were determined as follows: oats, buckwheat and sorghum proportion of 38∶31∶31（g/g/g）,maturing time of 34 min, first drying temperature of 110 ℃（10 min）, the reconstituted multigrain cereal prepared under these conditions exhibited the best sensory quality.