On the occasion of the recent normative framework established after the approval of the Regulation of functioning and legal regime of the centres of foreigners' internment (RD 162/ 2014), the exercise of religious freedom there is analyzed by them in them retained. The interest of the topic is takes root, principally, in the increasing plural religious profile of the incomer ones. For this purpose, there will be examined the legal configuration of the religious freedom and its application in this situation of privation of freedom. In sum, the agreement happens with the convention of the religious confessions as key instrument, and the need of a positive performance of the center for its suitable guarantee.