Second language acquisition (SLA) as a sub-branch of applied linguistics has been researched by Chinese and foreign scholars for over 40 years, but few researches have been done on its implications for Business English teaching which needs more language teaching theories to support. This paper makes a review of related studies, and puts forward a systematic framework of exploring the essential implications of second language acquisition theory for Business English teaching in current China based on the SLA concepts of input hypothesis, output hypothesis, affective filter hypothesis, learner-centered approach, natural language context, communicative approach, etc. along the whole process of Business English teaching. It concludes that the theory of SLA is applicable for Business English teaching in China and has essential implications in Business English curriculum design, teaching material selection, teaching method selection, and performance evaluation.