This study synthetically investigates the mediating effect of trust climate and the moderating effect of management’s HRM philosophy regarding the influence of employee turnover rates on organizational performance. In addition, reflecting the need for multi-level research that considers social contexts such as climate, affective commitment which is an individual level variable was also investigated as another dependent variable. The core of this study is that it explained the complex relationship between these variables based on social information processing theory, interactionist perspective, social comparison theory, attribution theory, social exchange theory and perceived organizational support theory. This study predicted that a low level of trust climate will be created from high turnover rates because remaining employees raise suspicions about the organization by interacting with each other. It was also expected that this kind of trust climate will have negative impact on organizational performance and affective commitment by the logic of social exchange. As a result of studying 275 companies and their 7,170 employees, using data from the 4th year(2011)’s HCCP(Human Capital Corporate Panel) of the Korea Research Institute for Vocational Education & Training(KRIVET), it was found that the employee turnover rates had a significantly negative effect on both organizational performance and affective commitment, and the trust climate mediated these relationships. However, it was found that management’s HRM philosophy did not moderate the relationship between turnover rates and trust climate. These results show that low organizational performance is not necessarily due to the loss of human and social capital from turnover but can also be affected by a negative trust climate created by the remaining employees. In addition, the fact that turnover rates had a negative impact on the affective commitment of individual employees by mediating trust climate means that employees are inevitably affected by the climate as they belong to a social context like an organization. This study is meaningful in that it revealed that the trust climate can function as one of the important mediators in the relationship between turnover rates and organizational performance, which has been considered a black box in the meantime. Meanwhile, this study’s theoretical and practical implications, limitations, and directions for future research were also discussed.