This qualitative study aimed to examine Iranian language teachers' mindsets about language learning and teaching, and the ways in which their mindsets influenced their educational practices. The participants of this study were 20 Iranian language teachers who taught general English courses at private language institutes in a city in central Iran. The data were collected through conducting semi-structured interviews with the participants. The qualitative content analysis was conducted, and the main themes and categories were extracted. The results revealed that teachers had categorical (fixed or growth) or mixed mindsets (both fixed and growth mindsets). Moreover, the results showed that teachers' mindsets influenced teachers' pedagogical strategies, homework assignment, and their praise type. The findings show that it is important to raise teachers' awareness about their mindsets and the effects they might have on their teaching strategies and the feedback/praise they give to their students.