Interspinous fusion device (1) comprising a central body (10) defining a longitudinal direction (11) and configured to be inserted between two adjacent spinous processes; a proximal body (30) and a distal body (40), opposite to each other with respect to the central body and configured to relatively translate towards each other along the longitudinal direction; a pair of proximal jaws (21, 22) and a pair of distal jaws (23, 24) opposite to each other with respect to the central body and spaced apart from each other along the longitudinal direction, and having a first end connected by hinges (21a, 22a, 23a, 24a) to the proximal body or to the distal body, and also having a second end configured to abut against a spinous process; an actuation system (50) of the proximal and distal bodies (30,40), which are configured to be percutaneously actuated to cause a relative translation and a rotation of the jaws about the proximal body and the distal body, so as to move from a closed configuration to an open configuration of the jaws.