A closure system for a drawer cabinet, comprising: - locking means that can be configured in at least a releasing position, wherein it enables the opening of a drawer of a drawer cabinet, and a locking position, wherein it prevents the opening of the drawers of the drawer cabinet; - activation means that can be activated by means of the command of an operator and that is active on said locking means for moving the locking means between said locking and releasing positions, said activation means being configured so as to take on an open position, corresponding to the releasing position for releasing the locking means, and a closed position corresponding to the locking position for locking the locking means; - enabling means designed for enabling and disabling movement of the locking means between said locking and releasing positions; said activation means being configured in such a manner as to bring itself automatically from the open position to the closed position within a pre-established time interval, following release of a command for opening the activation means by the operator regardless of the status of the enabling means, and wherein said locking means comprises a translatory motion device that is active between said locking and releasing positions, characterized in that said activation means comprises: - a button, mechanically acting upon said translatory motion device and movable by means of translatory motion between said open and closed positions so that translatory motion of the button slidingly drags the translatory motion device and - a contrast spring associated with the button and designed for keeping the button pushed towards the closed position, said pre-established time interval corresponding to the time needed for the button to return from the open position to the closed position under the effect of said contrast spring, wherein said enabling means comprises a key lock with a translatable cylinder and wherein said translatable cylinder defines said button; said key lock being configured so as to lock and release manual translatory motion of the button on the part of a user, wherein said key lock is configured in such a manner as to allow for the following positions: - a first position, with the cylinder extracted and not rotated, for enabling the translatory motion of the button; - a second position, with the cylinder extracted and rotated, for preventing the translatory motion of the button; the position being such that rotation of the cylinder is not possible with the button in the pressed position, and wherein said activation means comprises spacer means designed for determining a position of maximum translatory motion of the cylinder of the key lock; said position of maximum translatory motion of the cylinder defining said open position and being in advance of a hypothetical limit position of the cylinder suitable for allowing rotation of the key so as to prevent permanent activation of the release of the locking means. - locking means that can be configured in at least a releasing position, wherein it enables the opening of a drawer of a drawer cabinet, and a locking position, wherein it prevents the opening of the drawers of the drawer cabinet; - activation means that can be activated by means of the command of an operator and that is active on said locking means for moving the locking means between said locking and releasing positions, said activation means being configured so as to take on an open position, corresponding to the releasing position for releasing the locking means, and a closed position corresponding to the locking position for locking the locking means; - enabling means designed for enabling and disabling movement of the locking means between said locking and releasing positions; - a button, mechanically acting upon said translatory motion device and movable by means of translatory motion between said open and closed positions so that translatory motion of the button slidingly drags the translatory motion device and - a contrast spring associated with the button and designed for keeping the button pushed towards the closed position, said pre-established time interval corresponding to the time needed for the button to return from the open position to the closed position under the effect of said contrast spring, wherein said enabling means comprises a key lock with a translatable cylinder and wherein said translatable cylinder defines said button; said key lock being configured so as to lock and release manual translatory motion of the button on the part of a user, - a first position, with the cylinder extracted and not rotated, for enabling the translatory motion of the button; - a second position, with the cylinder extracted and rotated, for preventing the translatory motion of the button;