This paper describes an intelligent engine stop-start strategy for vehicles equipped with this system. This controller, at first stage, monitors the history of vehicle movement and quantifies the traffic condition. At the second stage, based on this traffic degree it adjusts one controller parameter named waiting time that is the time that has to pass for engine to shut down. This way, this strategy prevents engine from shutting down in very heavy traffic condition where too frequent stop start occur, when instead of improving fuel economy it results in increasing fuel consumption. In fact, this control strategy is addressing one problem of the conventional stop-start systems where regardless of traffic condition based on a simple if-then algorithm stops and starts the engine.