本文基于行动研究探讨大学英语学习环境下教师在学习者自主中的作用以及教师如何中介学生自主能力发展。通过对自主学习模式和课堂教学模式的对比分析， 及对自主学习模式的行动干预结果分析，发现: 1) 教师是大学英语学习环境下学习者自主的必要构念: 2) 基于行动研究范式的教师介入有助于提高学习者自主学习能力、 心理和行为。文章最后讨论本研究结果对实施大学英语自主学习的启示。

Based on an action research study， this paper explored the role of the teacher in the development of learner autonomy and approaches that teachers used to intervene into students' development of learner autonomy in the College English teaching environment． Through the comparison between the self-access learning mode and the classroom teaching mode and the analyses of the intervention effects， this paper found that: 1) the teacher is the construct of learner autonomy in the College English teaching environment; and 2) teachers' intervention through action research helped develop students' language autonomy． Implications for programs that aim to promote learner autonomy are discussed accordingly．