Abstract: According to the cost and benefit data of dairy farming in Henan Province and China listed in Collection of National Agricultural Product's Cost and Benefit, calculating the product efficiency in different dairy farming scales with Data Envelopment Analysis, after comparing the results, it is concluded that from 2014 to 2015,the average product efficiency of scatter-feed cow in Henan Province is larger than that of small-scale farming, large-scale farming, and medium-scale farming and that of national scatter-feed cow; and the average product efficiency of small-scale,medium-scale and large-scale farming in Henan Province is smaller than that of national dairy. On the facts of dairy farming in Henan, advice of promoting dairy farming transformation to large-scale farming is raised.