The aim of the article is to analyze the not previously discussed problem of the application of legal provisions regarding the movement of dogs and cats by Polish animal shelters to other EU Member States. This matter is regulated in EU law, as well as in Polish law, and its complexity, overlapping standards and emerging uncertainty regarding their application by state administration justifies taking up this topic. The analysis covers veterinary requirements for shelters from which dogs or cats are moved to other EU Member States, as well as requirements relating to the identification and health of the animals themselves. An important problem that has been revealed is the application of regulations regarding the approval of this type of establishments by official veterinarians without giving priority to EU law. Polish authorities that approve animal shelters require operators running these establishments to meet the Polish law requirements, which, however, do not result from EU regulations. These may lead to discrimination against Polish establishments running animal shelters.