Wireless Sensor Networks (WSNs) offer an excellent opportunity to monitor environments, and have a lot of interesting applications in warfare. Intrusion detection in Wireless Sensor Network (WSN) is of practical interest in many applications such as detecting intruder .The intrusion detection is defined as a mechanism for a WSN to detect the existence of inappropriate, incorrect, or anomalous moving attackers In this paper, I consider the cluster based architecture according to two WSN models: homogeneous and heterogeneous WSN. Furthermore, I derive the detection probability by considering two sensing models: single-sensing detection and multiple-sensing detection. In this Intrusion detection model we are going to track and detect Intrusion in a Homogenous and Heterogeneous Wireless Sensor Networks (WSN) using the intrusion distance and detection probability with various Tracking and Detection models.