Abstract: GPS and Inertial Navigation Systems (INS) are used today in automobile navigation and tracking systems to locate themselves in Four Dimensions (latitude, longitude, altitude, time). However, GNSS or GPS still has its own bottleneck, such as the long initialization period of Precise Point Positioning (PPP) without dense reference network. For navigation, a number of selected LEO satellites can be equipped with a transmitter to transmit similar navigation signals to land users, so they can act like GNSS satellites but with much faster geometric change to enhance GNSS capability, which is named as LEO constellation enhanced GNSS (LeGNSS). This paper focuses on Low Earth Orbit navigation and anti-theft tracking system in automobiles that represents a framework which enables a navigating vehicle to aid its Inertial Navigation System when GNSS or GPS signal becomes unusable. Over the course of following years LEO satellite constellation will be available globally at ideal geometric locations. LEO Satellite aided Inertial navigation system with periodically transmitted satellite positions has the potential to achieve meter-level-accurate location. Keywords: LEO constellation, LEO enhanced GNSS (LeGNSS), Precise Point Positioning (PPP), Inertial Navigation System (INS), Precise Orbit Determination (POD)