The topic of this thesis is guilt in criminal law, so it deals primarily with the issue and conceptual definition of guilt in criminal law as a key element of responsibility for criminal acts. Guilt is a fundamental concept that defines the degree of responsibility of an individual for the committed act and thus determines the legal consequences. Guilt in criminal law refers to the subjective attitude of the perpetrator towards the committed criminal act. It includes the elements of consciousness and will, which are necessary for determining responsibility. The process of determining guilt is included in all stages of the criminal procedure, from the investigation to the passing of the verdict and sentencing. Understanding the interrelationship between the culpability of a criminal act and the criminal procedure is essential for a fair and efficient judicial system. Criminal proceedings begin with the investigation phase, which aims to gather evidence and establish facts related to the committed criminal act. The determination of guilt at this stage is based on preliminary evidence that points to the existence of intent or negligent behavior of the perpetrator. Investigators analyze motives, collect testimony and conduct forensic analysis to reconstruct events and determine potential culpability. After the end of the investigation, if there is enough solid evidence, the state prosecutor files an indictment against the suspect. The trial is the central stage of the criminal procedure in which the evidence and arguments of the defense and prosecution are presented before the court. After the trial, the court issues a verdict that can be acquittal or conviction. In the case of a guilty verdict, the court must clearly explain how the elements of guilt were determined. Sentencing is the last stage of the criminal procedure, in which the punishment for the perpetrator is determined based on the established guilt. When imposing a sentence, the court takes into account the purpose of criminal law, which includes retribution, prevention, rehabilitation and protection of society. The punishment must be proportional to the gravity of the criminal offense and the degree of guilt, taking into account all relevant circumstances established during the procedure.