According to theoretical model of Cognitive-Attitude-Behavior,situational experiment will be used in this paper to explore differences and internal mechanism of effect of different brand misconducts types on perceived risk,trust and purchase intention.It is found in the study that perceived risk caused by product misconducts is stronger than that of non-product misconducts,while it is just the opposite for trust and purchase intention,in the meanwhile,consumers trust has a mediating effect on the relationship of perceived risk and purchase intention in both types of misconducts.