An actuation device which is configured for moving fender members used to protect boats comprising - a support frame, which is configured to be coupled with the wall of said boat and which includes a box-like enclosure configured to be housed in a containing compartment formed in the hull of the boat and having a front inlet, which is surrounded by a protruding frame suitable to be externally placed close to said wall of said boat in order to ensure water tightness, - a fender member, configured to re-enter in or come out from said front inlet, in order to be placed in a non-use/use position, - moving means, which are coupled with said support frame and which support said fender member in order to move it between said non-use position and said use position, in which said fender member at least partially protrudes from said wall of said boat in order to protect it from accidental impacts during mooring and/or landing, - wherein said moving means include a flexible and expandable hollow body operatively connected with pneumatic activation means which place it between a rest position, in which the volume defined by said flexible and expandable hollow body is minimal and said fender member is placed in said non-use position, and an operating position, in which said flexible and expandable hollow body is filled with air, so that the volume defined by said flexible and expandable hollow body is maximum and said fender member is placed in said use position, - wherein in said rest position said flexible and expandable hollow body is included in the size of said support frame and said fender member re-enters within said box-like enclosure through a front mouth of said box-like enclosure, thus re-entering within the overall dimensions of said boat, - characterized in that connection means, associated with said flexible and expandable hollow body with which they cooperate, are configured to support said fender member, said connection means including an elastic shock-absorbing coupling, placed inside and at an axial zone of said hollow body, suitable to deaden the impacts suffered by said fender member. - a support frame, which is configured to be coupled with the wall of said boat and which includes a box-like enclosure configured to be housed in a containing compartment formed in the hull of the boat and having a front inlet, which is surrounded by a protruding frame suitable to be externally placed close to said wall of said boat in order to ensure water tightness, - a fender member, configured to re-enter in or come out from said front inlet, in order to be placed in a non-use/use position, - moving means, which are coupled with said support frame and which support said fender member in order to move it between said non-use position and said use position, in which said fender member at least partially protrudes from said wall of said boat in order to protect it from accidental impacts during mooring and/or landing, - wherein said moving means include a flexible and expandable hollow body operatively connected with pneumatic activation means which place it between a rest position, in which the volume defined by said flexible and expandable hollow body is minimal and said fender member is placed in said non-use position, and an operating position, in which said flexible and expandable hollow body is filled with air, so that the volume defined by said flexible and expandable hollow body is maximum and said fender member is placed in said use position, - wherein in said rest position said flexible and expandable hollow body is included in the size of said support frame and said fender member re-enters within said box-like enclosure through a front mouth of said box-like enclosure, thus re-entering within the overall dimensions of said boat, - characterized in that connection means, associated with said flexible and expandable hollow body with which they cooperate, are configured to support said fender member, said connection means including an elastic shock-absorbing coupling, placed inside and at an axial zone of said hollow body, suitable to deaden the impacts suffered by said fender member.