The confluence of contemporary terrorism and organized crime has caused a debate on the crime-terror nexus in academic circles.In terms of the classification of the two concepts,scholars put forward three viewpoints:combining the two concepts into one,establishing a more detailed classification system,or completely breaking the binary division between terrorism and organized crime.In terms of their relationship,the academic circles consider the two concepts easy to cooperate,difficult to cooperate or in mutual competition,among other contradictory viewpoints.In terms of the transformation between the two,scholars point out that the factors contributing to the transformation of terrorist organizations to criminal groups may include economic temptation,power competition among organizations and the interaction between terrorist organizations and the government.The government's crackdown is the main reason for the transformation of criminal groups into terrorist organizations.The lack of empirical research is the main reason why scholars have not reached a consensus on almost all the important issues in this field,and the immense difficulty of obtaining data is the main factor that causes this phenomenon.In order to make up for the deficiency in data acquisition and provide a new research perspective for the international security research,future research in this field should focus more on methods and swift from the current approach based on motives.