The purpose of this research was to investigate the effectiveness of instruction of metacognitive knowledge on academic stress in high school female students. This research method is quasi experimental with pretest and post test. Given this, 37female first grade students (19 subjects in experimental group and 18 subjects in control group) were randomly selected using multi-stage cluster sampling. Measurement device used was academic stress questionnaire and metacognitive knowledge strategies were instructed to subjects during 8 sessions. The data were analyzed by descriptive statistics and multi-covariance and covariance. The results showed that instruction of metacognitive knowledge have significant effect on reduce of academic stress.
