Evidence of proof has been clearly distinguished by the Iranian legislator in two area, civil and criminal. Some evidences such as confession, testimony and knowledge of the judge have been specified in civil and criminal regulations with the least difference in details, but some evidences such as Qasame have appeared with a narrow interpretation only in criminal regulations. Although criminal law has distinguished itself from civil law in terms of its purpose, nature and judicial system, the idea of using the same evidence system in the common domain of the two areas is not unlikely. For this reason, with the provision of the feasibility to demand Diya in the civil tribunals, invoking Qasame can be proposed as one of the means of proving the claim. In this research, with a descriptive and analytical method, while using the judicial procedure, the possibility to file a lawsuit for demanding Diya in the civil tribunals is endorsed, and following the adoption of this approach, the civil judge uses Qasame as a proof in the case of Diya, which is the intersection point between the civil and criminal tribunals, will be assessed. The findings of the research show that the non-exclusivity of evidence in civil matters, the absolute ability of the judge in handling all legal matters based on fixed rules, and the possibility of expanding the thinking of criminal proceedings to civil proceedings are the grounds for accepting Qasame as evidence in a civil tribunal; However, due to the incompetence of the civil court in dealing with the essence of the crime, the need for a narrow interpretation of the function of Qasame institution and the monopoly of some criminal tools to the criminal courts, the function of Qasame as a proof in the civil court should be abandoned.