Although countries in South-East Europe (SEE) traditionally use less pesticide in agricultural production than more developed countries in Europe, primarily due to the extensive character of their agriculture production, it is important to find the level of pesticide use because their usage can have a significant negative impact on the environment, health and social costs. The main objective of this paper is to find the correlation between pesticide use and economic development in SEE countries. In that context, the model for determining economic factors that can influence pesticide use is constructed and estimated. The results show that gross domestic product and precipitation had a positive impact on pesticide use, while farm size, trade openness, and membership in the European Union (EU) had a negative impact. This paper makes a significant contribution to the literature of pesticide use in SEE countries and answers questions which are significant for determining economic factors. This is important for policymakers, especially in countries that are candidates for EU membership, countries that should adopt EU legislation of pesticide use and establish new agri-ecological measures.