Load-sensing control device for priority valves, comprising: - a body inside which is formed at least a first seat communicating with at least a supply line, connectable to pumping means of a working fluid, with at least an output line (5, 6) of the working fluid connectable to at least a user point, and with at least a load-sensing line adapted to send inside the first seat itself a pressure signal corresponding to the working pressure of at least a priority user point; - at least a spool accommodated in a sliding manner inside said first seat to control the flow rate of the working fluid towards said output line (5, 6), on said spool acting at least a first chamber communicating with said load-sensing line and at least a second chamber connectable with said priority user point, where said first chamber acts on a first extremity of said spool and said second chamber acts in contrast with said first chamber, and where inside said first chamber are accommodated elastic means adapted to push said spool in contrast with the action applied by said second chamber; - at least a third chamber communicating with said first chamber and acting on a portion of a second extremity of said spool opposite said first extremity and said second chamber acting on the remaining portion of said second extremity, the useful surfaces acting on said spool from mutual opposite sides corresponding to that of said remaining portion; characterized in that said second chamber acts on a control element accommodated in a sliding manner inside a second seat located in one of said spool or said body and adapted to rest against a bottom wall of said first seat or against the said second extremity of the spool respectively, the surface of said control element facing the said second chamber itself corresponding to the useful surface of said remaining portion. - a body inside which is formed at least a first seat communicating with at least a supply line, connectable to pumping means of a working fluid, with at least an output line (5, 6) of the working fluid connectable to at least a user point, and with at least a load-sensing line adapted to send inside the first seat itself a pressure signal corresponding to the working pressure of at least a priority user point; - at least a spool accommodated in a sliding manner inside said first seat to control the flow rate of the working fluid towards said output line (5, 6), on said spool acting at least a first chamber communicating with said load-sensing line and at least a second chamber connectable with said priority user point, where said first chamber acts on a first extremity of said spool and said second chamber acts in contrast with said first chamber, and where inside said first chamber are accommodated elastic means adapted to push said spool in contrast with the action applied by said second chamber; - at least a third chamber communicating with said first chamber and acting on a portion of a second extremity of said spool opposite said first extremity and said second chamber acting on the remaining portion of said second extremity, the useful surfaces acting on said spool from mutual opposite sides corresponding to that of said remaining portion;