Positions of bearings and prefabricated crack of asphalt concrete（AC） semi circle specimen were adjusted to determine cracking resistance under different loading modes. Three point bending（SCB） tests were conducted at 4 temperatures and 5 loading modes, and the rules of the critical stress intensity factor（CSIF） and its variation with temperature and loading mode were obtained, which show that temperature and loading mode have obvious effects on the anti cracking performance, the crack resistance increases with the decrease of temperature, and the minimum fracture resistance occurred under a specific mixed mode Ⅰ/Ⅱ fracture mode. So, a pure type Ⅰ or Ⅱ fracture test will over estimate the crack resistance, its critical stress intensity factor should be tested under a Ⅰ/Ⅱ mixed mode.