In this study, we conducted a simulation experiment to examine how client hostility and empathy (personal distress) affect emotional exhaustion, performance, and physiological indicators in human service workers. Fifty-two university students listened to a recorded dialogue between a client (who had applied for counseling) and a receptionist. The client's hostility was manipulated (hostile vs. non-hostile), and the participants were given to believe that they would receive a call from the same client as reception staff after the listening session. Their emotional exhaustion, physiological indicators before and after listening to the dialogue, and empathy traits were measured. The results indicated that (a) the hostile client exhausted the participants more than the non-hostile client did. (b) Personal distress and hostility had a significant interactive effect on performance. (c) Physiological indicators were not affected by hostility and empathy. The relationships among these results and the mechanisms of burnout were discussed.