The rapidly growing of data center energy consumption rates are contributing to concern about energy conservation. Reasonable airflow organization is an effective way to reduce the cooling system energy consumption and to upgrade the energy utilization efficiency. Comprehensive and accurate analyses are important for airflow organization optimization. This paper presents the entransy dissipation analysis method to analyze the influences of hot and cold air mixing and cooling air distributions on data center heat transfer process. The thermal resistance based on entransy dissipation is used to define three indexes to evaluate hot and cold air mixing, cooling air distributions and the integrated heat transfer performance. A sample data center is studied with the analytical results showing that the smaller the entransy-dissipation-based thermal resistance is, the lower the average heat source temperature will be. Thus, the minimum thermal resistance principle is applicable to the analysis and optimization of data center heat transfer process. The three indexes can be used to guide the improvement and optimization of airflow organization. (C) 2013 Elsevier Ltd. All rights reserved.