Job satisfaction can affect one’s work continuity and well-being. Therefore, job satisfaction is of great importance to management. The purpose of this study was to identify the most important factors that affect the job satisfaction of College English teachers in Hochiminh City. Once such factors are identified, efforts can be made to regulate the increase and decrease of college teachers’ job satisfaction. A survey about the three most important factors to the teaching career was carried out and the in-depth interviews with college English teachers were conducted. The participants in the survey were college English teachers in Hochiminh City. The participants in the in-depth interviews were seven tenured College teachers and the Rector of a College in Hochiminh City. Data collected through the survey were sorted by the frequency of their importance. Data collected through in-depth interviews were tape-recorded or noted down and then categorized into themes of working conditions and work itself. Results revealed that to the college English teachers whose salary and working conditions were at an acceptable level, the factor that affected their job satisfaction was Direct Supervision and some other factors. The research findings from the direct interview put forward a conclusion that Direct Supervision was the most important factor that could regulate the increase and decrease of college teachers’ job satisfaction.