The invention relates to a liquid leakage detection method of an energy storage battery. The liquid leakage detection method of the energy storage battery comprises the following steps: respectively setting a gas detector at an air outlet of each battery box, detecting electrolyte gas concentration evaporated by the energy storage battery in the corresponding battery box through the gas detector;obtaining difference between numerical values of electrolyte gas concentration evaporated by the energy storage battery and detected by gas detectors on two neighboring layers of the battery boxes through subtraction, consequently obtaining a difference value of multiple groups of electrolyte gas concentration; respectively judging whether the difference value of multiple groups of electrolyte gasconcentration reaches a preset concentration difference value, and according to a judging result, judging whether the energy storage battery leaks. The liquid leakage detection method of the energy storage battery can effectively and accurately detect liquid leakage situation of the energy storage battery in an energy storage battery cabinet, can effectively prevent the electrolyte of the energystorage battery from decomposing lots of combustible gas under an unmonitored state, and greatly improves safety of an energy storage system. The invention also discloses a liquid leakage detection system of the energy storage battery.