Intrusion detection plays an important role in today's computer and communication technology. As such it is very important to design time efficient Intrusion Detection System (IDS) low in both, False Positive Rate (FPR) and False Negative Rate (FNR), but high in attack detection precision. To achieve that, this paper proposes IDS model based on Fuzzy Logic. Proposed model consists of three parts, Input Reduction System (IRS), which uses Principal Component Analysis to reduce the dimensions of the system from 41 to 10, Classification System, which uses Fuzzy C Means to create data clusters based on training data and Pattern Recognition System based on Nearest Neighborhood method, which classifies new-coming data records to their respective clusters. Based on different attack types, the system performance in classification process is different and the best performance is achieved for PROBE attack, with 99.3% success rate, and the best performance in pattern recognition is achieved for U2R with 58.8% of success rate.