The shortage of sugar supplies for consumption domestically in Thailand had arisen in 2006 and again in 2010. Since 1970s, Thailand was one of the top-ten sugars exporting and producing country of the world. The main objective of this study is to analyze the production efficiency of the sugar mills in each region of Thailand while examine and understand the sugar shortage situation in Thailand occurred in the year 2010. The Data Envelopment Analysis Program (DEAP) method is employed and the annual data of 2006-2010 (MY2005/06-2009/10) are utilized. The result from the analysis show that the average index of relative efficiency of the sugar industry in Thailand is equal to 0.881 and 7 factories (14.58%) is in the efficiency group. The Northeast region is the most efficient, with four efficient factories. The factories in the North and the Central region are relatively lower in efficiency with 2 and 1 factories in the region, respectively. The Eastern region is relatively lowest in efficiency and consists of relatively small scale of factories. In addition, the result shows that by using more capital can provided higher efficiency rate. This study indicates that sugar production should be promoted in the Northeastern region, the efficiency of sugar production should be improved in the Eastern region, and the capital intensive technique should be utilized to improve sugar production efficiency. While to handle with the future sugar shortage situation in Thailand, the sugarcane and sugar production and process should be more efficient, in both productivity and management issues.