The paper presents a proposal for the indicator used to assess the level of complexity of the logistic structure. Presented synthetic index takes into account 27 factors grouped into five thematic areas: organization and logistics management, inventory management, warehousing, packaging and reverse logistics and transportation management. The proposed indicator was used to assess the complexity of the logistic structure in the Polish agri-food companies, taking into account the number of employees in enterprises and the sectors. Also the existence and strength of the relationship between the size of the company and the industry on the one hand, and the complexity of the logistics structure on the other were examined.