Teachers’ language mindset has recently emerged as a growing area of research, with evidence suggesting its relevance to English language learning through its impact on students’ academic performance and motivation. This study aims at understanding the language mindset of post-basic Omani EFL teachers and their perceptions of student foreign language learning abilities. In addition, an investigation was conducted into the correlation between their language mindset and their views regarding students’ abilities to learn the English language. The study also attempts to gain insight into how teachers’ choice of teaching approaches is guided by the types of language mindset they hold. The research combines a mixed method design for data collection. The quantitative data were collected using an online close-ended questionnaire to evaluate the language mindsets of 204 post-basic Omani EFL teachers and their perceptions of student language learning abilities. The qualitative data were collected through in-depth, face-to-face semi-structured interviews that consisted of four scenarios, each with its pertinent questions. The findings show that Omani EFL teachers generally tend to possess mixed beliefs relevant to both fixed and growth language mindsets, and these are reflected in their approach to instruction. Likewise, they have a combination of fixed and growth beliefs about students’ language learning abilities. The data also reveal that teachers’ perceptions towards students’ language learning abilities are more positive the more growth-focused they become. Implications and recommendations for further study were addressed.