It is essential for Airline Service Department to educate students and give a guide line to its students enough to develop their own career in the airline service field. Recognizing the importance of Self-Leadership, Problem Solving Ability in order to enforce Career Preparation Behavior of students, this study planes to examine the relationship among Self-leadership, Problem Solving Ability, and Career Preparation Behavior. For the sake of enhancing Career Preparation Behavior, this study undertook a theoretical approach followed by a statistical analysis. The self-Communication method was adopted to collect the data during January in 2020. The valid survey of 320 students majoring in Airline Service was selected and analyzed by SPSS 20.0 and AMOS 20.0 program. The results of findings were as follows: First, both Behavior-focused strategies and Constructive thought pattern strategies of Self-leadership shows significant effects on Problem Solving Ability. Secondly, only Natural reward strategies of Self-Leadership shows a significant effects on Career Preparation Behavior. Thirdly, Problem Solving Ability doesn't show any direct effects on Career Preparation Behavior. However, Problem Solving Ability plays mediation effects between Self-Leadership and Career Preparation Behavior. It is required to adapt appropriate tools such as their self-leadership program, problem solving activities and consulting activities in order to enhance Career Preparation Behavior.