动机在二语习得的过程中起着至关重要的作用,是影响二语学习者学习成效的重要因素之一。深入研究二语学习动机,既有助于教师更好地了解学生的学习需求和心理状态,从而制定更有针对性的教学策略,也有助于学习者更好地认识自我状态,从而采取更有效的学习方法,提升学习效率。第二语言学习动机研究历经了四大阶段,包括社会心理学阶段、认知–情境阶段、过程导向阶段及社会动态阶段。本文拟对各个阶段形成的理论成果进行介绍,并对动机研究中现存的问题进行反思。Motivation plays an important role in second language acquisition and is a critical factor influencing learning achievements of second language learners. Therefore, in-depth research on L2 motivation not only helps teachers to better understand students’ learning needs and mental states, so as to formulate more targeted teaching strategies, but also helps learners to better understand themselves, so as to adopt more effective learning methods and improve learning efficiency. In general, it has gone through the following four periods, including the socio-psychological period, the cognitive-situated period, the process-oriented process and the social-dynamic period. Following this sequence, this review introduces the main theories during each period and reflects the existing problems in this field.