This paper examines the cause-and-effect relationship among intrinsic motivation, meta(cognitive) strategies and academic achievement in a group of four-year college students. The 82 participants took a fifteen-week English course, a mock TOEIC, and completed a questionnaire on intrinsic motivation and metacognitive strategies. T-tests and multiple regression analyses were conducted to determine relationships among all variables. The findings showed that, first, intrinsic motivation and metacognitive strategy were statistically significant predictors when comparing academic achievement between groups. Second, among metacognitive subcategories, learning method and learning purpose were statistically meaningful indicators of academic achievement. Finally, multiple regression analyses predicted that intrinsic motivation and metacognitive strategy have a cause-and-effect relationship in college students’ academic achievement. In conclusion, the cause-and-effect relationship among intrinsic motivation, metacognitive strategies and academic achievement was found to be definite. Implications for the practical class and further effective studies are suggested.