Needle safety device for a hollow medical needle, comprising - a needle safety element (2) movably arranged on an axis (1.1) of the needle in a prepared position, - said needle security element has a proximal posterior wall (2.1) in which there is formed an opening (2.2) for the passage of the needle axis, in which the edges of the opening are coupled with the axis of the needle in a protective position, and - that it has elastic arms (2.3, 2.4) that extend from the proximal posterior wall (2.1) in the distal direction, in which the arms are provided with a part (2.5, 2.6) of curved distal wall, which rests on the axis of the needle in the prepared position and overlapping on the tip of the needle in the protective position, in which - there are reinforcements (3a, 3b) arranged laterally of the arms (2.3, 2.4), whose reinforcements are joined in the proximal ends with the proxi posterior wall (2.1) badly of the needle safety element, characterized in that the reinforcements are connected to each other at the distal ends by means of a support (3c) extending transversely to the needle (1) in front of the needle security element (2), - the reinforcements (3a, 3b) and the support (3c) surrounding the needle safety element (2) as a structure within which the arms of the needle safety element can move between the prepared position and the protection position.Dispositivo de seguridad de agujas para una aguja médica hueca, que comprende - un elemento (2) de seguridad de agujas dispuesto de manera desplazable sobre un eje (1.1) de la aguja en una posición preparada, - dicho elemento de seguridad de agujas tiene una pared (2.1) posterior proximal en el que hay formada una abertura (2.2) para el paso del eje de la aguja, en el que los bordes de la abertura se acoplan con el eje de la aguja en una posición de protección, y - que tiene brazos (2.3, 2.4) elásticos que se extienden desde la pared (2.1) posterior proximal en la dirección distal, en el que los brazos están provistos
