In the design process of fuzzy controller, its para meters’ setting and adjustments mainly rely on the experience of the designer, so traditional fuzzy controller desig n method has great limitations and uncertainties. I n this paper, a new fuzzy controller design method based on cat swa rm optimization (CSO_FC) is proposed. CSO_FC method is realized below: Firstly, weighting factor is introd uced to initialize query table. Then, cat swarm opt imization is used to optimize relative parameters of the controller, such as weighting factor and quantification factors .With the Optimized parameters, desired output is obtained. F inally, on the platform of the MATLAB software, tak ing temperature of the reactor as the controlled object , the proposed CSO_FC is simulated. The simulation result shows that it has good following performance and control precision.