Abstract: The present paper probed into the nature and components of metacognition. Based on the analysis of relevant ideas, metacognition was defined as "the cognitive regulation of the ongoing cognitive activities", which included hoe components: metacognitive knowledge, metacognitive experience, and metacognitive skill. In addition, the role of every component played in metacognitive activities was discussed, and the relationship among the components was described in a schematic diagram.

Key words: metacognition, metacognitive skill, metacognitive knowledge, metacognitive experience