Increasing the economic security of enterprises through its components, in particular, with the intensification of the technical and technological component, is an important task of every enterprise in the agricultural sector of the economy. The purpose of the study is to form methodological approaches to determining the costs of production and application of organic fertilizers in order to reduce them by making shorter transport costs while improving the technical and technological component of the economic security of the enterprise. The main generally accepted methods of planning the production cost of the agricultural sector have been considered. It has been established that the use of models based on closed production cycles with a high level of recycling of biogenic elements is recognized as a promising approach to the assessment of agricultural production organization systems. To substantiate and systematize the formation of the costs of an agricultural enterprise for the production of organic fertilizers, taking into account the relationships of production units, economic and mathematical models have been developed: planning the production of organic fertilizers and planning the cost of organic fertilizers. The methodological apparatus of application of the developed models for a specific enterprise is proposed. The joint use of the developed economic and mathematical models for planning the production of organic fertilizers and planning the cost of organic fertilizers will allow planning the technological processes of organic fertilizer production in connection with the processes of the main production of agricultural products. Operational planning will reduce the cost of organic fertilizers, increase profitability and profitability from the cultivation and sale of crop production, and therefore ensure the growth of economic security of the enterprise.