An anti-theft and safety mechanism for bottles is described, comprising a case, first locking and unlocking means, and second locking and unlocking means adapted to be actuated, when locking, through a manual action, after the mechanism has been inserted onto the neck of a bottle and, when unlocking, as consequence of the unlocking action exerted on the first locking and unlocking means, allowing the removal of the mechanism from the neck of the bottle, wherein the first locking and unlocking means comprise a hook which is adapted to fasten a collar of the bottle, and the second locking and unlocking means comprise a first half-circular element adapted to be moved in contact with the neck of the bottle preventing the access to the tip of the hook.