In Mongolia, teachers' attitudes towards large-scale assessments have been a largely uncovered area. Therefore, this paper focuses on examining the general overview of English language teachers' belief about state-level assessments, and their reflection on teaching practices. Participants of this study were 307 teachers of primary and secondary school teachers, and 36 of them were English language teachers of Dornod province in Mongolia. Independent sample t-test was used to explore how English teachers change their instructions in teaching English compared to other subjects teachers. Result showed that they usually search for more effective teaching methods, take less liberty on how they design their lessons, reduce instructional content, and focus more on Educational standards. As a result of a correlation analysis, English language teachers' assessment view is significantly related to the content of the assessment that is designed by teachers in a class. Based on the results, it can be concluded that teachers focus more on the assessment content that they design for progress and final exams. They prefer to prepare students for this assessment by making them practice the test items that are similar to the school achievement test items during classes. Understanding the reasons for ineffective instructions can help policy makers and teachers to change the assessment content and its accountability, and would also help to improve their classroom instructions to have better learning outcome.