The interrogation of the defendant is a significant evidentiary action governed by the provisions of the Criminal Procedure Code (Art. 85 - Art. 90). The performance of the interrogation allows the defendant to provide their defence and make a statement on the criminal offense they are charged with, while the proceeding authority thereby receives a direct statement of facts concerning the criminal offense, from the person who, as a rule, has the best knowledge of how it had been perpetrated. In Serbian law, the term defendant is a general term used to denominate a suspect, an accused person, defendant and convicted person (Art. 2, para. 1, item 2 of the CPC), and the rules of the CPC pertaining to the interrogation of the defendant as an evidentiary action are applicable in a number of procedural situations, depending on the stage of criminal proceedings. In the context of our topic, we will deal with procedural situations where the rules governing the interrogation of the defendant as an evidentiary action are implemented during the questioning of a suspect. First and foremost, this is an opportunity for the suspect to be questioned by the police or the public prosecutor's office as early as during the preinvestigation proceedings in accordance with the rules governing the interrogation of the defendant. This is possible only in exceptional cases and under specific conditions: that the suspect agrees to give their testimony and that both their consent and statement are given in the presence of a defence counsel (Art. 289, para. 4 of the CPC). Second, the provisions governing the interrogation of the defendant will always be applied by the public prosecutor when questioning the suspect during the investigation stage (Art. 300, para. 1 of the CPC). Third, these provisions are applied by the public prosecutor in summary proceedings, where an investigation is not conducted, but only certain evidentiary actions (Art. 499, para. 2 of the CPC). Generally speaking, the defendant's interrogation process evolves through three stages, which is what determined the structure of this paper. The first stage implies the beginning of the interrogation and consists of three steps, namely, making contact with the defendant, followed by the acquisition of personal information from the defendant and, ultimately, presenting allegations to the defendant on the criminal offense they have been charged with, their rights and obligations. The second stage is related to the very course of providing a statement on the criminal offense which the defendant has been charged with and it consists of a stage in which the defendant gives an undisturbed statement and a stage of questioning the defendant. The recording of the testimonies and the completion of the interrogation represent the third stage of this evidentiary procedure. The aim of the paper is to present criminal rules regulating the interrogation of a suspect by the police or the public prosecutor's office, in situations when this interrogation is conducted as an evidentiary action in accordance with the provisions of the Criminal Procedure Code.