This article is an attempt to examine the impersonal constructions in Bulgarian in terms of the choice and use of active and passive voice. The investigation is based on the theories of Bondarko, Hrakovski and Melchuk about the voice and the Dowty’s theory about the protoroles (Protoagens and Protopatiens). We tried to combine their conceptions together and, according to the specifics of the impersonal sentences in Bulgarian, to create a model for description and to find out where is the place of each type of impersonal predicates in this model.