A system for diagnosing a contactor life using contactor coil current, the system comprising: a voltage measurement unit measuring voltage of a contactor coil for a contactor; a current measurement unit measuring current of the contactor coil; a temperature measurement unit measuring a temperature of the contactor coil; characterised by a confirmation unit adapted to confirm a real-time resistance value, a real-time value of the voltage, and a real-time value of the current of the contactor coil based on a temperature measurement value measured through the temperature measurement unit; a storage unit adapted to store an average of the measured values of the current measured when the contactor operates to correspond to a predetermined number of times; and a determination unit adapted to determine whether a life of the contactor is deteriorated based on whether the average value stored in the storage unit exceeds a predetermined threshold current value, wherein the storage unit is adapted to store an average of the measured values of the current measured when the contactor operates 50 times as a first average value and to store an average of the measured values of the current measured when the contactor additionally operates 10 times after 50-time operations as a second average value, and wherein the determination unit is adapted to determine that a malfunction occurs in the contactor to generate a warning signal when at least one of the first average value and the second average value exceeds the threshold current value, and to deliver a second average value additional storing signal to additionally store the second average value in the storage unit as determining that the malfunction does not occur in the contactor when the first average value and the second average value do not exceed the threshold current value. a voltage measurement unit measuring voltage of a contactor coil for a contactor; a current measurement unit measuring current of the contactor coil; a temperature measurement unit measuring a temperature of the contactor coil; characterised by a confirmation unit adapted to confirm a real-time resistance value, a real-time value of the voltage, and a real-time value of the current of the contactor coil based on a temperature measurement value measured through the temperature measurement unit; a storage unit adapted to store an average of the measured values of the current measured when the contactor operates to correspond to a predetermined number of times; and a determination unit adapted to determine whether a life of the contactor is deteriorated based on whether the average value stored in the storage unit exceeds a predetermined threshold current value, wherein the storage unit is adapted to store an average of the measured values of the current measured when the contactor operates 50 times as a first average value and to store an average of the measured values of the current measured when the contactor additionally operates 10 times after 50-time operations as a second average value, and wherein the determination unit is adapted to determine that a malfunction occurs in the contactor to generate a warning signal when at least one of the first average value and the second average value exceeds the threshold current value, and to deliver a second average value additional storing signal to additionally store the second average value in the storage unit as determining that the malfunction does not occur in the contactor when the first average value and the second average value do not exceed the threshold current value.