Animal-based models used in biomedical sciences allow to perform research that, conducted on humans, would be highly problematic because of bioethical and technical issues. Contemporary researchers race can lead to abuse, hence the need for special law regulations regarding this subject. This necessity reflected both in the EU and Polish legislation, and is rooted in the philosophical and moral achievements of Europe. EU legislation in this case takes the form of directives implemented in the legal systems of the member states. Polish tradition of legislative approach to animal-based research is long. In 1959 the wide attempt to regulate this matter was undertaken. Until 2005, the nature of the matter had been regulated by the Polish animal protection law. Currently, details concerning animal-based-research are regulated by the animal experiments law (2005). The elapsed time since enactment allowed doctrine and judicature to reveal capabilities and vulnerabilities of the law.