Since the role of teacher success is highly important in the adequacy of teaching and learning, the present study intended to examine the role of two factors, namely language teachers' credibility and nonverbal immediacy, with respect to their success across intermediate and proficient levels. To this end, 135 EFL students of Golestan University voluntarily participated in this study. First, an Oxford Quick Placement Test (QPT) was administered to identify the differences in participants' language proficiency level. Then, three questionnaires, namely the Nonverbal Immediacy Scale (NIS), the Source Credibility Scale (SCS), and the Characteristics of Successful Teachers Questionnaire (CSTQ), were distributed among the respondents. Using Cronbach's alpha and correlational analyses, first, the reliability of the questionnaires and the associations among NIS, SCS, and CSTQ were examined. The results of Pearson correlations reveal that there are significant positive correlations among all three scales. These findings were also confirmed by Structural Equation Modeling (SEM) results; teacher perceived success is predicted positively and significantly by both credibility and nonverbal immediacy. Findings of the present study suggest that teachers' credibility and nonverbal immediacy are highly beneficial to their perceived success. This study also outlined which elements of teachers' credibility could be more useful for their success. The implications are also discussed.