The purpose of this paper was to determine the role of dairy cooperatives which are a crucial factor in reducing losses of dairy products at the distribution stage of the dairy production chain in the Lubelskie voivodeship. The research was conducted on local data provided by one of the largest Polish supermarket chains. In the Lubelskie voivodeship, dairy products are manufactured in 18 plants, including 14 dairy cooperative members. Basic dairy products are mainly supplied by local dairies, especially by dairy cooperatives. Operators based outside the Lubelskie voivodeship supply the majority of processed milk products. The greatest product losses are related to products supplied by dairies based outside the voivodeship. The main cause of dairy product loss in the supply chain was product expiry. On average, the largest share of expired products (excluding desserts) was noted for goods supplied by dairies based outside the voivodeship. As regards most products supplied from outside the voivodeship, their share in losses exceeds their share in sales (by a few or up to several dozen percent). The retail chain covered by this study mainly relies on a wide range of basic local dairy products offered by Lublin dairies, especially including dairy cooperatives. These suppliers continue to be an important link in the regional dairy chain.