Safety top balustrade for a car of a machine room-less elevator which moves in a hoistway, on a wall of which the controller of the elevator is secured, said balustrade comprising:—a fixed structure (21) comprising a plurality of vertical uprights (24) fixed at intervals near edge of the car roof (16) and at least two horizontal tubular guard rails (20, 30) fixed at different heights on the uprights, around the periphery of the car roof, except at the place which is in front of the controller (14) when the car is at the level of controller, in order to leave a passage (33) for direct access to the latter,—a mobile structure (34) comprising at least two horizontal bars (36, 38) which are telescopically mounted inside the tubular guard rails, so as to slide between an open position where the bars are inserted within the guard rails, to free said passage towards the controller, and a closed position where the bars are extended out of the guard rails, whereby said passage is obstructed.