本文利用兩階段隨機成本邊界模型研究中國全國性銀行及地方性銀行之X無效率,第一階段估計出中國銀行效率值並討論中國銀行是否存在規模經濟使得全國性銀行效率高於地方性銀行,其次檢驗中國銀行在加入WTO前後效率是否顯著提升。第二階段討論影響中國銀行無效率之因素。 研究結果顯示,全國性銀行並未如先前研究宣稱的具有規模效果而有較高的生產效率。至於WTO的影響方面,檢定結果指出在加入WTO前後無論是全國性銀行或是地方性銀行效率皆有所提升。而經由第二階段對於影響X無效率的估計可以發現,沿海銀行效率較內陸銀行為高。另外,資產規模對無效率具有正向影響,而銀行成立年數對於無效率值有負向的影響。 This paper applies two-stage stochastic frontier cost function to analyze the x-efficiencies of the nation wide and regional banks in China. In the first stage, we estimate the efficiency scores of China banks and discuss whether the economy of scale exists which makes the efficiency scores of the nation wide banks higher than those of the regional banks. Besides, we examine the impact of entering WTO. In the second stage, we discuss the factors which may affect the inefficiency of banks in China. The result shows that the nation-wide banks do not exists scale effect and have higher efficiency scores. As for the impact of entering WTO, the result proves that the nation wide and local banks are more efficient after entering WTO. In the second stage, we find that the coastwise banks are more efficient than the interior banks. We also find that the size of the assets has a positive effect of x-inefficiencies, while the age of the bank has a negative effect.