The organizational structure of multinational trade companies is tending to become more networked and flattened due to the rapid advancement of information technology and the ongoing changes in international forms. This transformation of the enterprise's leadership is also a result of the organizational structure change, and middle managers' competency requirements are continuously being raised. As the information era arrived, enterprise middle managers found themselves both responsible for transmitting information and knowledge from higher to lower levels and unable to process the vast amounts of data and knowledge required to make sound decisions.In addition to playing an increasingly important role in helping businesses achieve core competitiveness, middle managers are also receiving attention from a variety of academic disciplines, including economics, management, and other areas. Thus, a number of international trade enterprises must deal with the issue of survival and development in the increasingly complex global business environment in order to improve middle managers' competence as the starting point, to make middle managers' performance clear as the guide, and to increase the core competitiveness of international trade enterprises as the goal. In order to achieve this, this paper reviews the literature on middle manager competence both domestically and internationally. It does this by establishing a leadership competence research model and delving deeply into the impact of middle managers' leadership competence on work performance, as well as the importance of leadership support and trust in international trade enterprises. First, the structural characteristics of leadership competence in this study were identified, and the leadership competence scale in the Chinese context was constructed, based on the combing of the ideas and elements of middle managers' competence. According to the study, there are three components that make up leadership competency: professional competence, interpersonal communication competence, and leadership. The reliability of the key variable scales in the model was assessed. Second, it was confirmed that leadership competency has an impact on work performance. By using the classical scale to divide job performance into three dimensions — task performance, peripheral performance, and innovative performance— and by testing the validity and reliability of the classical scale using 380 questionnaires from middle managers of Chinese enterprises, it was determined that the determination of the dimensions of job performance was reasonable. Nine action routes may be created when there is a one-to-one correlation between the three dimensions of leadership competence and work performance. All of these action paths passed the test and demonstrated the beneficial impact that leadership competence has on job performance. Third, it was confirmed that leadership trust had a moderating role in the connections between job performance and leadership competencies. The moderating connections of professional competence, interpersonal communication skills, and work performance was mediated by leadership trust. Leadership behaviors and competencies are more often associated than independent. The study's data analysis results provide additional evidence that the connections between middle managers' leadership behaviors and competence is the same, and that the development of leadership behaviors will be aided by high levels of competence. The results of the mediation effects of professional competence, leadership competence, and interpersonal communication skills on task performance and innovation performance were partially mediated, fully mediated, and partially mediated, respectively, while the mediation effects on peripheral performance were not significant. Leadership trust demonstrated differential mediation effects when leadership competence acted on task performance and innovation. Lastly, it was established that leadership support had a moderating effect on the connections between work performance and leadership competency. The moderating effects of leadership support varied depending on the connections between work performance and leadership competency. While the moderating effects between the other five paths of the function of leadership competence on job performance were not significant, the moderating effects of leadership support were between task performance and leadership, between interpersonal communication competence and peripheral performance, between professional competence and peripheral performance, and between leadership and innovation performance. When adding leadership support as a moderating variable, the favorable effects of professional and interpersonal communication competence on peripheral performance are mitigated. Leadership support has the highest moderating influence between leadership and innovation performance. In conclusion, this work contributes to the field of leadership competence