Global Navigation Satellite System (GNSS) has become the most popular apparatus for generating navigation and positioning informationand ground vehiclessmartphones et al all rely on GNSS for obtaining high-precision navigation and positioning information.Howeverunder complex city environmentsGNSS signals are often blocked by the surroundingsand thus the GNSS receiver cant obtain adequate signalswhich may lead to big positioning errors or no output of navigation solutions.Vector Tracking Loops (VTL) use a Kalman filter to estimate the navigation and positioning solutionsand VTL is able to output positioning information with only one visible satellite.Howeverthe positioning errors will diverge over time.In order to improve the VTL performance under signal challenging environmentsthis paper proposes an altitude information aided VTL methodand the model is given.Field tests show that the positioning errors are obviously reduced in the two-minute experiment with the aid of altitude information.