The purpose of this study was to investigate ESP teachers’ perceptions of Business English courses. Specifically, this study aimed to explore how teachers planned Business English courses, how they developed students’ competence and skills, and how they continued their professional growth. A qualitative approach was used to frame the inquiry of this study. The participants were seven Business English teachers at one technological university in Southern Taiwan; four of them were from the Applied English Department and three from the International Business Department. Data were collected through interviews, classroom observations, and field notes. Major findings of the study were as follows: First, in course design, Business English teachers would develop students’ business knowledge and improve their English communication skills. Second, students’ English ability, business background knowledge, attitude, communication skills, independent thinking ability, and flexibility were all considered important by Business English teachers, with a view of helping students meet the needs of the job market. Third, teachers read relevant news or magazines to absorb new business knowledge, and attended business seminars or enrolled in short-term business programs to improve their teaching abilities. Fourth, some teachers agreed with the idea of increasing teaching hours of Business English in order to provide more professional training programs for students. Fifth, teachers suggested that instructors from industry could be hired as part-time Business English teachers to bridge the gap between classroom learning and the real world. Based on the findings of this study, the implications for Business English teaching and learning and suggestions for future research were addressed.