This paper presents a fuzzy system to discriminate speech signals from background. In our previous works, we had developed a method for speech classification. For speech classification, the universe of discourse is divided into two types, and each type is treated as a class. These are background and speech signals. The rectangular fuzzy system (RFS) is used to classify frames and integrate the rule-based approach. The variance of first detail and the third approximation can extract fuzzy classification rules. Experimental results demonstrate the superior performance to the conventional ones . The effectiveness of the proposed system is confirmed by the experimental results.