Using questionnaires and tests, this study explores the interactive effects among English speaking achievements and six learner characteristics, i. e., emotional intelligence, foreign language anxiety, motivation, working memory, language aptitude and cognitive style. The data analysis using structural equation modeling (AMOS 22.0) reveals the results that cognitive ability composed of working memory, language aptitude and cognitive style is the best predictor of learners English speaking achievements, and anxiety the second, that cognitive ability and emotional intelligence forms covariance, affecting together English speaking achievements, and that anxiety plays a mediating effect on the relationship between motivation and English speaking achievements.