This research is aimed at finding out the influence of lecturers' language style on students' academic self-efficacy in higher education in Indonesia. This research is conducted to describe the correlation between lecturers' language style and students' academic. As one of the aspects of forming academic self-efficacy, language style has an important role because someone who can get information verbally about his ability in mastering certain duty tends to do more efforts. In addition, it makes him more diligent in doing a duty. Also, language style positively increases the student's self-confidence and vice verse. This research involves seventy students who fill in the questionnaire about the lecturer language style and academic self-efficacy scale. Data were analyzed by using simple linear regression analysis. The result of the research shows that lecturer's language style has a coefficient of determination of 23.5% towards the students' academic self-efficacy. Finally, this research affirms that positive lecturer language style can improve the students' belief towards their ability while the negative language style can weaken the students' self-efficacy. This is supported by the statement of Pajares (2002) who state that the negative language style can easily weaken the students' self efficacy.