Device for realizing an underwater electrical connection comprising: - at least a male connector and at least a female connector mounted on a watertight container, the male connector comprising conductive elements and at least a control element , all elements having each a portion coated with an insulating material and, respectively, a free end acting as electrical contact for the power supply (E), and a free end acting as electrical contact for a control signal; - a battery comprised in a further watertight container; and - at least a relay ; characterized by comprising electronic boards located respectively on the side of the female connector and of the male connector communicating each other by means of the control element which is insulated from water and configured to: - detect the status of coupling / decoupling of the male connector , the female connector measuring, by means of the first electronic board , the voltage value V between the control element and the conductive element and monitoring the data transmission between the electronic boards ; - enable the relay and - disable the electrical current flow between the female connector and the male connector in each one of the following conditions: - when the voltage between the control element and the conductive element has a value V greater than a predefined threshold voltage V 0 measured by the first electronic board ; - when an interruption of communication between the electronic boards occurs; - when a water leakage in the watertight container occurs; - when a water leakage in the further watertight case comprising the battery occurs; - when an overcurrent occurs; - when an over-temperature occurs. - at least a male connector and at least a female connector mounted on a watertight container, the male connector comprising conductive elements and at least a control element , all elements having each a portion coated with an insulating material and, respectively, a free end acting as electrical contact for the power supply (E), and a free end acting as electrical contact for a control signal; - a battery comprised in a further watertight container; and - at least a relay ; characterized by comprising electronic boards located respectively on the side of the female connector and of the male connector communicating each other by means of the control element which is insulated from water and configured to: - detect the status of coupling / decoupling of the male connector , the female connector measuring, by means of the first electronic board , the voltage value V between the control element and the conductive element and monitoring the data transmission between the electronic boards ; - enable the relay and - disable the electrical current flow between the female connector and the male connector in each one of the following conditions: - when the voltage between the control element and the conductive element has a value V greater than a predefined threshold voltage V 0 measured by the first electronic board ; - when an interruption of communication between the electronic boards occurs; - when a water leakage in the watertight container occurs; - when a water leakage in the further watertight case comprising the battery occurs; - when an overcurrent occurs; - when an over-temperature occurs. - when the voltage between the control element and the conductive element has a value V greater than a predefined threshold voltage V 0 measured by the first electronic board ; - when an interruption of communication between the electronic boards occurs; - when a water leakage in the watertight container occurs; - when a water leakage in the further watertight case comprising the battery occurs; - when an overcurrent occurs; - when an over-temperature occurs. <EOS>