Abstract: The big hole and unscientific hole shape of sieve plate of movable sieve jig could lead to large amount, high ash of screening materials and handling diffi culty. On the basis of researching on screening mechanism, the authors carried out the optimization design of sieve plate structure, the arc wave shape hole sieve plate was designed by changing the shape and size of mesh sieve plate structure which could significantly reduce the sieve screening materials. The industrial comparison te sts with the application of arc wave shape hole sieve plate and straight rectangle hole sieve plate, the results showed screening materials content was reduced from 0. 36% to 0. 082%，reduced by 77. 2%, screening materials ash was reduced from 55. 51% to 38. 72%. The arc wave shape hole sieve plate could not only significantly re duce the amount of screening materials, but also reduce the screening material ash, which could simplify the disposition of screening materials.