This study was predominantly conducted to examine 280 eleventh-grade students’ appraisal of their speaking problems and potential influential factors at Tay Ninh high school, Vietnam. The data were garnered by 40-item questionnaire copies and analyzed by SPSS 22.0 for descriptive statistics (e.g. mean, standard deviation, and percentages) and inferential statistics (e.g. Beta and significance values). The findings of the study revealed that a greater part of the eleventh graders at this site frequently experienced linguistic problems of accuracy, fluency and appropriateness; alongside, many students also encountered with some non-linguistic problems such as inhibition, nothing to say, low participation, and mother tongue use. These speaking problems derived from two main influential factor domains, including internal (e.g. limited language input and topical knowledge, negative psychological states), and external factors (e.g. pressured performance conditions, rigid ELT curriculum, counter-productive ELT materials, inconvenient classroom environment, teachers’ inflexible roles, fixed teaching methods).