Many vehicles use stabilizer bars to increase the roll rate for satisfactory handling characteristics. Stabilizer bars are laterally mounted torsional springs that resist the vertical displacement of the wheels relative to one another. Vertical suspension rates are not increased when both wheels are deflected simultaneously; however, the stiffness of one wheel bump is increased. The analytical and experimental techniques for accurately estimating the roll stiffness of a stabilizer bar are presented in this paper. Three models of a stabilizer bar are designed as follows: torsional spring model, bushing model, and beam model. Based on quasi-static and vehicle dynamic analyses, we found that the beam model is the most efficient method to consider the twisting and bending of a stabilizer bar.