The discussion of the Common Agricultural Policy is ongoing. One possible scenario is the reduction of support of the Azorean farms. To compensate this loss of income, dairy farmers will improve the efficiency of their farms. This paper aims to estimate the efficiency values and the number of efficient farms in S. Miguel Island, which contributes with 75% of regional production. Milk production in the Azores represents 30% of the Portuguese. This research was going in 91 S. Miguel farms. The efficiency was estimated using the DEAP. Two models are available: considering whether or not subsidies as output. The Model I showed that 7 (7.69%) farms are efficient. The level of technical efficiency is 0.312, which means, it can be possible to reduce up to 31.2% of expenditures in consumption without penalizing production. The technical efficiency of 68.8% in Model I decrease to 63.7 % in Model II, in this study case, 5 (5.49%) farms are efficient. This study characterizes the structure of the farms, presents the DEA and the most relevant work in this area, and discussion of the results. Finally, there are the concluding remarks and bibliography.