The rules are the prescribed standards on the basis of which decisions are made for specific purpose. The rule is a statement that establishes a principle or standard, and serves as a norm for guiding or mandating action or conduct. The rule can be a conditional statement that tells the system how to react to a particular situation.This paper presents an rule reduction approach to reduce rules using decision matrix.We have also used this approach on dengue data set.The result shows that this approach produces effective and minimal rules.