The object of this study is concerned about the optimal design of the supporting frame in a twist screen. Twist screen is widely used for grading and screening materials in the fields such as coal-selecting, mining-selecting, building materials, electrical power and chemical industry, etc. It is composed of base, supporting frame, vibrator, screen, spring, trough, clamp and etc. Especially, supporting frame in twist screen are stressed by high load, mostly it is shock-type loads. Nevertheless, design of base is dependent on experience, and it will cause reliability reduction and cost increase. The supporting plate is composed by the upper plate, the bracket and etc. This research purpose is to propose and verify a method to achieve higher product quality, lower costs, and far less physical testing. In this study, design parameters used for optimization are the upper plate thickness(8㎜, 10㎜, 12㎜) and the bracket thickness(8㎜, 10㎜, 12㎜) in the supporting frame. The result showed that base weight reduced to maximum 25.8% when compared with the current twist screen.