A laundry washing machine, comprising: - a washing tub configured to be supplied with washing liquid for treating laundry; - a rotatable drum, in which laundry to be washed can be loaded, mounted in the washing tub; - a drain pump operable to selectively cause washing liquid located in the washing tub to be discharged; - an overflow control system (193, 194') for detecting an occurrence of an overflow condition of the laundry washing machine in which a level of washing liquid collected at the bottom of the laundry washing machine is equal to or higher than a predetermined threshold, and for driving the drain pump to discharge washing liquid from the washing tub in case an overflow condition has been detected, the overflow control system (193, 194') comprising a switching unit and a detection unit, wherein: - the switching unit comprises a switch having a first terminal connected to a terminal of an AC electric power supply and a second terminal connected to the detection unit, the switch being configured to electrically connect the first terminal with the second terminal in a closed configuration and to electrically insulate the first terminal from the second terminal in an open configuration, the switching unit being configured to switch the switch to the closed configuration when the level of washing liquid collected at the bottom of the laundry washing machine is equal to or higher than said predetermined threshold, characterized in that - the detection unit comprises a microcontroller for managing the operation of the laundry washing machine and is configured to detect an overflow condition occurrence and to drive the drain pump without involving the microcontroller to discharge washing liquid from the washing tub when the switch is in the closed configuration and the microcontroller is turned off or is in a sleep mode. - a washing tub configured to be supplied with washing liquid for treating laundry; - a rotatable drum, in which laundry to be washed can be loaded, mounted in the washing tub; - a drain pump operable to selectively cause washing liquid located in the washing tub to be discharged; - an overflow control system (193, 194') for detecting an occurrence of an overflow condition of the laundry washing machine in which a level of washing liquid collected at the bottom of the laundry washing machine is equal to or higher than a predetermined threshold, and for driving the drain pump to discharge washing liquid from the washing tub in case an overflow condition has been detected, the overflow control system (193, 194') comprising a switching unit and a detection unit, wherein: - the switching unit comprises a switch having a first terminal connected to a terminal of an AC electric power supply and a second terminal connected to the detection unit, the switch being configured to electrically connect the first terminal with the second terminal in a closed configuration and to electrically insulate the first terminal from the second terminal in an open configuration, the switching unit being configured to switch the switch to the closed configuration when the level of washing liquid collected at the bottom of the laundry washing machine is equal to or higher than said predetermined threshold, - the detection unit comprises a microcontroller for managing the operation of the laundry washing machine and is configured to detect an overflow condition occurrence and to drive the drain pump without involving the microcontroller to discharge washing liquid from the washing tub when the switch is in the closed configuration and the microcontroller is turned off or is in a sleep mode.