This research focuses on improving intrusion detection systems by combining support vector machine (SVM) and k-nearest neighbor (KNN) algorithms to reduce false positive rates. The experimental results, applied on the KDDCup99 dataset, demonstrate that the combined algorithm (CSVMKNN) outperforms both SVM and KNN in terms of performance, accuracy, and error rates. Ultimately, the CSVMKNN algorithm enhances the detection capabilities of network security systems against various types of attacks.