The ex officio test is a power conferred on the judge, stipulated in the COGEP, for direct intervention in the judicial process. The objective of this research is to carry out a legal analysis of the ex officio test within the Ecuadorian legislation. The methodology used obeys a qualitative approach, of a descriptive type with the phenomenological - comparative method. Among the main findings, it was determined that one of the conditions required of the judge is to request and justify the need for ex officio evidence at the preliminary or single hearing. Therefore, this power is part of legal certainty and guarantees of due process, because it is conferred by the Ecuadorian State through regulations. It is also concluded that the judge lacks the power to supply or omit facts, therefore, within the resolutions that he issues in the exercise of his functions, he is only attributed the provision of evidence for a duly substantiated opinion, with the purpose that, in the resolutions issued, justice is administered on the controversial facts and circumstances that have been proposed by the procedural parties.