Based on different motivation theories a study was conducted to examine the relationship between teachers' motivation and their instructional practices and its effect on students’ achievement motivation. The sample size included 45 teachers and 55 students of a private school. Separate questionnaires measuring teachers and students variables were used. The current study used correlation method and regression was run to analyze the data. The results from the current study do not support the findings of the previous researchers as it reported negative correlations for teachers’ motivation and their instructional practices. Also the relationship between teachers’ instructional practices and students’ achievement motivation was partially confirmed. This indicates that the teaching practices of the teachers are not always guided by their goal orientation or their implicit beliefs. Besides, it also implies that the goal orientation of the teachers is not the only determining factor for teachers to evaluate students’ abilities.