A refrigerating air-conditioning system comprising a refrigerating cycle by connecting an outdoor unit and one or a plurality of indoor units, with communication piping, the outdoor unit having a compressor, an outdoor heat exchanger, and throttling device, each of the indoor units including an indoor heat exchanger (9a or 9b) and a throttling device (7a or 7b), wherein the refrigerating air-conditioning system comprises: one or more of the indoor heat exchangers or one or more of the outdoor heat exchangers functioning as condensers; and judging means for judging a refrigerant leakage of the refrigerating cycle, on a basis of past data relating to a past refrigerant volume of the refrigerating cycle at a past time point and new data relating to a refrigerant volume at a time point after performing a plurality of times of stopping and starting up operations of the refrigeration since the past time point, characterized in that the judging means judges the refrigerant leakage only when an outdoor air temperature is within a predetermined range in comparison to an outdoor air temperature at a time of taking data to be compared in the judging operation for the refrigerant leakage and when a predetermined time has elapsed from the time of taking the data, wherein the judging means for judging the refrigerant leakage calculates a liquid-phase area ratio on the basis of a plurality of parameters, the liquid-phase area ratio being a ratio of a liquid-phase volume to an entire volume of the one or more of the indoor heat exchangers or one or more of the outdoor heat exchangers functioning as the condensers, and compares the calculated liquid-phase area ratio with a past calculated result saved as history data to judge a refrigerant leakage, and the liquid-phase area ratio A L % is calculated by a formula below A L % = ∑ k = 1 n Q j k × − Ln 1 − SC k dT c k × dT c k × Cp r k Δ ⁢ hco n k ∑ k = 1 n Q j k where SC is a super-cooling rate of the refrigerant at an outlet of each condenser, dTc is a difference between an outdoor temperature and a condensing temperature, Cpr is a liquid-specific heat at constant pressure of the refrigerant, Δhcon is a difference of enthalpies at an inlet and the outlet of each condenser, Qj( k) is a heat exchange capacity of each condenser, k is an ordinal number indicating each of the condensers, and n is a total number of the condensers. one or more of the indoor heat exchangers or one or more of the outdoor heat exchangers functioning as condensers; and judging means for judging a refrigerant leakage of the refrigerating cycle, on a basis of past data relating to a past refrigerant volume of the refrigerating cycle at a past time point and new data relating to a refrigerant volume at a time point after performing a plurality of times of stopping and starting up operations of the refrigeration since the past time point, characterized in that the judging means judges the refrigerant leakage only when an outdoor air temperature is within a predetermined range in comparison to an outdoor air temperature at a time of taking data to be compared in the judging operation for the refrigerant leakage and when a predetermined time has elapsed from the time of taking the data, wherein the judging means for judging the refrigerant leakage calculates a liquid-phase area ratio on the basis of a plurality of parameters, the liquid-phase area ratio being a ratio of a liquid-phase volume to an entire volume of the one or more of the indoor heat exchangers or one or more of the outdoor heat exchangers functioning as the condensers, and compares the calculated liquid-phase area ratio with a past calculated result saved as history data to judge a refrigerant leakage, and the liquid-phase area ratio A L % is calculated by a formula below A L % = ∑ k = 1 n Q j k × − Ln 1 − SC k dT c k × dT c k × Cp r k Δ ⁢ hco n k ∑ k = 1 n Q j k where SC is a super-cooling rate of the refrigerant at an outlet of each condenser, dTc is a difference between an outdoor temperature and a condensing temperature, Cpr is a liquid-specific heat at constant pressure of the refrigerant, Δhcon is a difference of enthalpies at an inlet and the outlet of each condenser, Qj( k) is a heat exchange capacity of each condenser, k is an ordinal number indicating each of the condensers, and n is a total number of the condensers.