In this study the author tries to assess the effects of Theme-based Oral Approach (TOA) on the oral English proficiency of non-English majors as well as students' leaning motives and interests resulted from the approach in EFL class of China. The study follows the quantitative and qualitative method in light of questionnaire, interview, class observation with the causal-comparative study between treatment group and control group. The result shows that a majority of students with TOA improved their oral English learning more than those with Traditional Teaching Method (TTM). It also finds that TOA is able to motivate the students to speak in class and a certain percentage of students can overcome their psychological problems in expressing ideas. The findings are that TOA affects students' achievement in a favorable way which provides some theoretical, methodological and practical implications.