Abstract: Based on Bandura-s self-efficacy theory, thi s paper tries to explore the ways of improving our college English teaching, fro m both internal and external causes to enhance students- sense of self-efficac y. This paper holds the view that the internal aspects play a determining role i n students- sense of self-efficacy and the external factors have an impact on students through the internal ones. The joint effort of internal and external fa ctors is conducive to the enhancement of students- self-efficacy and the impro vement of their English learning.