Along with the rapid development in Call Center industry in China, more and more people work in Call Center. Due to 24hour&7days continue operation needs, it is very common that Call Center agent are facing high work stress, strict evaluation, limited career development, low pay and so on. Call Center agent’s work stress and mental health problems gradually attracted the attention of managers and researchers. The concept of Psychological Capital provides a new angle for thepeople developing of Call Center. Therefore, examine the Psychological Capital of Call Center agent and to explore whether Psychological Capital moderate the associations between work stress and stress reaction,work stress and job satisfaction, work stress and work performance will help to find a new way on Call Center agent people development. This research investigated 318 Call Center agents by using Enterprise staff work stress questionnaire, short version of Minnesota Satisfaction Questionnaire, work performance questionnaire which edited by Chinese researchers and Psychological Capital questionnaire in Chinese version. SPSS 16.0 was applied to analyze data. The result is showing below: (1) Call Center agents’ Psychological Capital is significantly negatively correlated with stress reaction, whereas it is significantly correlated with job satisfaction and performance, (2) Psychological Capital moderates the relationship between work stress and job satisfaction. Base on research of the impact of Psychological Capital between work stress and job satisfaction, whatever the work stress is high or not, Call Center agent with high psychological capital is engaged by high job satisfaction; but when work stress increased, the job satisfaction of Call Center agent with high psychological capital decreased relatively faster, even on this result, the job satisfaction of these staff keeps high level. (3) There is no found on the moderate role of Psychological Capital among work stress and stress reaction and work performance, which implies more study may needed in the future.