Blended Learning Theory is in a form of e-learning combined with face-to-face learning (He Kekang, 2003). It is believed that Blended Learning Theory has advantages of combining various teaching methods to obtain the best complementary strengths and learning effect. This paper intends to study the origin, the unique advantages, such as the sharing of information resources, providing an open environment for autonomous learning, exchanging feedback in time and displaying achievements publicly. At the same time, it gives some suggestions to optimize the teaching effect when Blended Learning Theory is applied to college English teaching and learning on dif-ferent aspects: The college should be well equipped with good multimedia network facilities; the functions of teachers should be clarified, includingdesigningthe teachingcontent and mode, organizing the teaching process, guiding the learners’autonomous learning and evalu-ating the learning outcomes; the responsibilities of learners should be specified, including developing an initiative attitude of college Eng-lish learning, changing the emphasized aspects in College English learning, taking active part in the whole process. Last but not the least, both teachers’and learners’abilityofusingmultimedia technologyshould be developed. Blended Learning Theory is in a form of e-learning combined with face-to-face learning (He Kekang, 2003). It is believed that Blended Learning Theory has advantages of combining various teaching methods to obtain the best complementary strengths and learning effect. This paper intends to study the origin, the unique advantages, such as the sharing of information resources, providing an open environment for autonomous learning, exchanging feedback in time and displayingiencechanged. effect when Blended Learning Theory is applied to college English teaching and learning on dif-ferent aspects: The college should be well equipped with good multimedia network facilities; the functions of teachers should be clarified, includingdesigningthe teachingcontent and mode, organizing the teaching process, guiding the learners’ autonomous learning and evalu-ating the learning outcomes; the responsibilities of learners shoul d be specified, including developing an initiative attitude of college Eng-lish learning, changing the emphasized aspects in College English learning, taking active part in the whole process. Last but not the least, both teachers’and learners’abilityofusingmultimediatechnologyshould be developed.