The source of law, the case-law of the European Court of Human Rights (hereinafter – the ECtHR), is playing an increasingly significant role in the practice of judicial proceedings in Ukraine. The activities of the ECtHR significantly affect the implementation of the principle of the rule of law in Ukraine in criminal proceedings. Therefore, the phenomenon of judicial precedent and the application of ECtHR practice in criminal law requires comprehensive analysis. The work aims to study the case law and practice of the ECHR in criminal law, problems of theory and practice of application of court precedents by national courts, and ways to solve them. The research methodology consists of such methods as historical and legal; comparative law; formal and logical; empirical; cognitive; method of analogy; synthesis method; method of analysis. The value of ECtHR decisions is that such decisions, more quickly than other criminal procedural means, make adjustments to the law enforcement process of public authorities, thus improving the mechanism of criminal procedural regulation to guarantee conventional and constitutional human rights. In addition, the recognition of the case law of the ECtHR as a source of law is necessary for the adaptation of national legislation of Ukraine to the legislation of the European Union. Although legal precedent is not officially recognized as a source of law in Ukraine, the decision of the ECtHR recognizing case law can be considered in Ukraine as a rule of law.