The main goal of this study is to investigate the relationship between epistemological beliefs and modeling skill of engineering students at Shiraz University. Statistical population was all engineering colleges’ students that by multistage cluster random sampling, 166 students of various majors were selected. The instruments of this study included “Epistemological Beliefs Inventory” (Schraw et al, 2002) and “Engineering Modeling Self-Efficacy Scale “(Yildirim, 2010) ) that after calculating validity and reliability distributed between the sample and gathered. Data analyzed by SPSS 20 and LISREL 8.54 software’s and for analyzing the methods of descriptive statistics like correlation and inferential statistics like independent T-test and one way anova were used and model was analyzed by SEM. The results indicated: 1) there is significant difference between the mean of quick learning and simple knowledge of male and female students. 2) There is no significant difference between students’ epistemological beliefs and their modeling skill based on their majors. 3) Higher years students have more complex epistemological beliefs and more modeling skill. 4) Epistemological beliefs of students are positive and significant anticipant of their self- efficacy in modeling skill.