With the rapidly increasing awareness on environmental issues, a competition of eco-friendly car development among vehicle manufacturers has become so intense. In fact, decent numbers of modern production vehicles which equipped with low fuel consumption means in various ways have been around in the world today. Since each vehicle manufacturer proposes brand-new vehicle systems one after another, vehicle types become significantly diversified and each one shows different characteristics indeed. On the other hand, these changes in requirements over vehicle performance bring corresponding changes in the development of tires suitable for a variety of the latest eco-vehicles.Recent tire requirements can be basically represented by compatibility between low Rolling Resistance (RR) and other performance while pursuit of RR reduction results in poor force and moment characteristics in general. Therefore, in order for realizing a substantially eco-friendly tire which simultaneously offers appreciable drivability along with decent performance in necessity, investigations of a next generation tire concept in terms of a tire dimension beyond common knowledge has been done.In this study, a size effect in terms of Rolling Resistance Coefficient (RRC), Cornering Power (CP), Stiffness, and Weight has been investigated through numerical simulations from tire deformation mechanism points of view , experimental analysis with actual tires as a verification by indoor measurements , and vehicle tests at proving ground . Through the series of research activities, one of the directions of next generation tire sizes is proposed and the future work of this concept is discussed as well.