This study explores the effects of World Englishes teaching practice in improving EFL learners’ self-confidence in English-speaking performance (SCIESP) with a mixed methodology design comprising both qualitative and quantitative approaches. Data were gathered through a survey with the Self-Confidence in English-speaking Performance Questionnaire, students’ reflective notes, and focus group interviews. Two teaching classes with no significant difference in self-confidence were randomly chosen as the experimental class (EC) and control class (CC). The two classes shared the same teaching implication except that the EC had four lectures on World Englishes while the CC got four lectures on English History. After one semester the research team surveyed students’ SCIESP again. The result showed a remarkable improvement in students’ SCIESP in EC than in CC. It was found that World Englishes teaching contributed significantly to increasing students’ SCIESP.
