The objective of this article is to analyze the socioeducation as a device of disciplinary power. To fulfill its purpose, it was necessary to analyze the life stories of a former inmate from the socioeducational system in the Southeastern region of Brazil, considering the socioeducational measures of internalization. The qualitative nature of the study adopted the biographical method with a male subject. In the process of the data production phase, meetings and conversations were held, which provided in-depth interviews. The stories reported were analyzed using content analysis technique, creating two subsequent categories. It is concluded that the socioeducation is a device, therefore, it is part of a power game, articulating power relation strategies and produce a discourse that has rules of conduct for managing the lives of inmates. The socioeducation is a device that circulates a disciplinary power, which is expressed through elements / instruments, such as the normalizing sanction, discipline, squaring up, examination, surveillance, hierarchical look and knowledge generated on the individual. The socio-educational spaces are watched in their entirety, so the inmate is meticulously inserted to be located, controlled, examined, distributed, docile and useful.