In order to evaluate the impact of Sasobit on asphalt, the 2%,3%,4% and 5% Sasobit by mass of asphalt are blended into two types of base asphalts (Pen 60/80 and SBS modified asphalt).The mixed asphalt will be called as Sasobit modified asphalt in this study. The 15°C, 25°Cand 30°Cpenetration, the softening point, the 60°C and 135°Cviscosity, the 5°Cductility of Sasobit modified asphalt are tested. The temperature susceptibility of Sasobit modified asphalt is evaluated by using PI, VTS, PVN25-135 and PIR&B. The linear relationships between PI and PIR&B or VTS and PVN25-135 are confirmed. As the addition of Sasobit can differently change the viscosity or rheology of Sasobit modified asphalt under different temperature, it has been shown that the temperature susceptibility of Sasobit modified asphalt become better within the normal temperature range (0°C~50°C) but become higher within the high temperature range (60°C~135°C) as the additive content increases. It has been proved that Sasobit have a different impact of asphalt’s temperature susceptibility at different temperature range. So it is not appropriate to express the temperature susceptibility of Sasobit modified asphalt using a conventional index PI. This study suggests that PI and PVN can be used as indicators of the temperature susceptibility of Sasobit modified asphalt within the normal temperature range and high temperature range respectively.