Abstract: It’s an inevitable development trend of agricultural industry in major grain producing areas to conduct moderate scale management for the new agricultural operating units. It also plays an important role in promoting the urbanization and agricultural modernization in China. Taking the modern agricultural machinery cooperatives in major corn producing regions of Heilongjiang Province as an example and based on the survey data from field interviews in these regions, this paper analyzed the production efficiency and the moderate scale management by data envelopment analysis (DEA) and discussed the influencing factors of the typical sample production efficiency. Results show that 27.2% of modern agricultural machinery cooperatives are DEA efficient and the moderate scale management of sample cooperatives under current conditions is 873.3-966.7 hm2. In addition, the insufficient output caused by low production and management levels is the major factor that influences the production efficiency of these regions. Under the assumption of reasonable allocation of resources, appropriate expansion of planting scale plays a positive role in promoting agricultural productivity of these regions. Based on the research results, as well as the problems in the scale production process of agricultural machinery cooperatives, including unreasonable quantity of inputs and low utilization rate of large agricultural machinery, this paper suggests to strengthen the learning awareness, to organize members to participate in agricultural machinery and agricultural technology training regularly, to regulate the production management, to implement standardized production, to establish the rental platform of agricultural machinery, and to improve the utilization rate of large agricultural machinery.