Interspinous distractor for percutaneous implantation comprising a central body (10) and two couples of stabilizears (14a, 14b; 14c, 14d), hinged at the end of the body (10) in order to rotate from a closed position, which assists the percutaneous implantation of the distractor, to a spread apart position, which limits its movement stabilizing it in the interspinous gap. Means are provided for causing the rotation of the stabilizears that can be operated percutaneously, in particular, by means of cam shaped elements sliding axially and adapted to engage a cam-shaped surface, or by a system of tie members, and special tools. With respect to the known distractors it can implanted end extracted percutaneously and in a much easier way.