It has been established that the efficiency of agriculture, as the central link of the agro-industrial complex, has a multi-purpose nature and can be represented as a system of republican, regional or territorial and economic efficiency. The concept of cluster effects is defined. In the development of the above, the principles for assessing the effectiveness of cluster formations are formulated. It has been established that under the assessment of the effectiveness of the organizational and economic mechanism of clustering, it is important to understand the analysis of all types of results in accordance with the goals of creating a cluster. At the same time, various cluster organizations in the agro-industrial complex can have a wide range of goals: ensuring sustainability, increasing production volumes, minimizing costs, etc. In this regard, the assessment of the effectiveness of the functioning of the cluster should be carried out in a comprehensive manner: a) from the standpoint of specific organizations included in the association; b) from the standpoint of the effectiveness of the functioning of the cluster as a whole; c) from the standpoint of the compliance of the cluster's goals with the methods of achieving them; d) from the standpoint of the consistency of the cluster's activities with the macroeconomic tasks of the agro-industrial complex.