An efficient system of economic organization is important part of modernization agriculture, which arouses an argument about what the division is between the functions and margins of family and market organization in the emerging modern agriculture of China. Based on the experience and examination on developed agriculture, it is found that family farms are the fundamental units of agricultural operation, that long-term hiring labors mainly takes place in livestock sectors, that the agricultural modernization degree has irrelevance to the land size of farms, and that it is widespread of agricultural specialization and cooperative organizations constructed by family farms. Theoretically, subjecting to the pattern of agriculture and efficiency of market institution, it is optimal to take family farms as main bodies of modern agricultural organization system, and to form specialization service enterprises and cooperative organizations to compensate family farms’ incapability in getting economies of specialization and scale. Thus, in the ongoing process of constructing agricultural organization modernization of China, China should support the growth of specialization service organizations and cooperative organizations based on families and family farms and should carefully use the policy on enlarging agricultural scale by hiring labors.