This study adopt input orientation data envelopment Analysis approaches to evaluate the operational efficiency for major international airports in terms of the top 20 ranking by total passengers handling in Asia region in 2008. Unlike the most the other airport literature researches only using the one-stage DEA to measure the efficiency, in this study, two-stage, the extension of DEA, adding the concept of the intermediates product, separate the airport operation into airport capital side and airport capability side, is applied to evaluate the two-side efficiency of each airport under the assumption of constant returns to scale, variable returns to scale, scale efficiency and super efficiency model by employing four inputs, four intermediate products and two outputs. The result of this study shows that the China Shenzhen Baoan airport is the best airport in overall technical efficiency in different stages. It indicates that the operation of small size airports (category by the passengers handling) are run more efficiency than the large one. In addition, by two-stage DEA analysis, the airport capital usage is better than in capacity utilization. It found that the China Beijing Capital airport is good in airport infrastructure usage but the capacity utilization is not enough. Finally, the number of increasing return scale airports are more than the decreasing return scale airports among Asia region (e.g. Taiwan Taoyuan airport), therefore, the expansions of facility and capacity in those increasing return scale airports are worthy to invest to promote the operational efficiency and its competitiveness.