Abstract The present study examines the mediating role of self-efficacy in the relationship between Holland personality traits and entrepreneurial behavior of students at the University of Engineering of modern technologies of Quchan. The research method is descriptive and correlational and structural equation modeling. The statistical population is all students of the University of Engineering of the New Technology of Quchan in 2016-2017 and numbered 713 people. In this research, 250 randomly selected samples were selected based on Cochran formula. The tools used were Zampetakis & Moustakis (2007), The Personality Types of Holland Questionnaire (1958) and Muris 's Self-efficacy Scale (2001). Pearson correlation coefficient and structural equation modeling were used to analyze the data. SPSS-22 and AMOS-22 software were used in all analyzes. The findings showed that self-efficacy has a direct relationship with entrepreneurial behavior and plays a mediator role in the relationship between the personality traits of Holland and entrepreneurial behavior. (χ2=0.20, GFI=0.91,AGFI=0.93,CFI=0.91,PNFI=0.92,RMR=0.10,RMSEA=0.06(.In other words, regardless of the personality types of the Holland, with the Enter of self-efficacy into the equation, the attraction of individuals to entrepreneurial behavior becomes greater. Therefore, to create entrepreneurial behavior, we need to create and strengthen the behavioral characteristics of the personality types of Holland and self-efficacy.