Abstract: A prefabricated panel for buildings and constructions adapted to be interconnected by mortise-and-tenon coupling with other panels, comprising on at least one of its faces a series of projections (2, 7) followed by tenon couplings (3, 8) and/or mortise couplings (4, 9) in form of protuberances and recesses, at least one of the walls of said protuberances or recesses being resilient and thus facilitating a snug force fit between them when conveniently opposing the faces of two panels, the height of said projections (2, 7) being such that it determines a separation between the opposite faces of the two panels which forms a hollow chamber. The projections (2, 7) with tenon couplings (3, 8) and the mortise couplings (4, 9) are distributed at such a distance to each other that they offer interstitial gaps (11) through the free hollow space between panels. The interstitial gaps (11) of said hollow chamber allow to arrange therethrough different ductings and wirings in all directions.