The scientific article is devoted to the definition of certain features of the procedure for conducting a pre-trial investigation in criminal proceedings of foreign countries. The origins of the separation of the «preliminary investigation» as a separate stage of the criminal process are established, as well as the relationship of national legal traditions and types of legal systems with the corresponding standards inherent in the criminal process is traced.
 The analysis of the criminal procedural legislation of the Federal Republic of Germany, the Kingdom of Spain, Great Britain and the French Republic was carried out. The main aspects of the pre-trial investigation and inquiry of the Federal Republic of Germany have been studied. It has been established where criminal proceedings begin, how the interaction between prosecutors and police officers is configured, which is free evidence. Attention is focused on the types of suspicions depending on the degree of probability and functional purpose.
 It was determined that the pre-trial investigation as an independent stage of criminal proceedings, according to the Criminal Procedure Law of Spain, is always the first in the criminal process. However, at the same time, the inquiry is in no way formally separated from the pre-trial investigation. The prosecutor and the investigating judge are united with the common goal of identifying the person who committed the crime and collecting the necessary evidence. The specifics of this stage depending on the type of proceedings are also indicated.
 The characteristic features of criminal proceedings in Great Britain, which do not include the stage of pre-trial investigation at all, are considered. Despite the possibility of the defense party to collect evidence independently, the police's activities are considered extra-procedural, and therefore all the factual data collected by them need to be presented to the magistrate and their further confirmation.
 The position and procedure for starting an investigation under French law is outlined. Her criminal process considers inquiry and preliminary investigation as separate independent stages. First of all, an inquiry is conducted, then a criminal prosecution is initiated, after which a preliminary investigation begins.
 The conclusion of the article emphasizes the need for coordinated work of law enforcement agencies based on the principles of the rule of law, legality and justice. The necessity of applying the experience of foreign countries in improving the pre-trial investigation of Ukraine is argued.