Rapid development of social network theory provides new perspective for the study of behavior of terrorist organizations. Due to the covertness of terrorist activities, the absence of individuals and relationships often occurs in the construction of interpersonal relationship network of terrorists using social network theory, thus affecting the effectiveness of analysis. This paper proposes a method for constructing covert terrorist networks based on interactive relationship records and combining hypothesis and inference, and carries out empirical study combining typical terrorist activities within the borders. Study results show that key figures and missing figures obtained according to analysis and evaluation of constructed networks are consistent with reality. This shows that the combination of hypothesis and inference and interpersonal relationship records is a feasible way to improve the construction of terrorist social network model.