An ice making system comprising: a tank for storing a medium to be cooled; an ice making machine that is configured to cool the medium to be cooled and makes ice; a pump that is configured to circulate the medium to be cooled between the tank and the ice making machine; a de-icing mechanism that is configured to perform a de-icing operation of heating and melting the medium to be cooled in the ice making machine; and a control device configured to control operations of the ice making machine, the pump, and the de-icing mechanism; wherein the ice making machine includes: a cooling chamber in which to cool the medium to be cooled; a blade mechanism configured to rotate in the cooling chamber to disperse the ice; and a detector configured to detect a locked state of the blade mechanism, wherein the control device is configured to operate the de-icing mechanism when the detector detects the locked state of the blade mechanism, characterized in that the control device is configured to stop the blade mechanism when the detector detects the locked state of the blade mechanism, and in that the ice making system further comprises a temperature sensor for detecting a temperature of the medium to be cooled discharged from the cooling chamber, wherein the control device is configured to stop the de-icing operation when the temperature detected by the temperature sensor for detecting a temperature of the medium to be cooled discharged from the cooling chamber exceeds a predetermined temperature. a tank for storing a medium to be cooled; an ice making machine that is configured to cool the medium to be cooled and makes ice; a pump that is configured to circulate the medium to be cooled between the tank and the ice making machine; a de-icing mechanism that is configured to perform a de-icing operation of heating and melting the medium to be cooled in the ice making machine; and a control device configured to control operations of the ice making machine, the pump, and the de-icing mechanism; wherein the ice making machine includes: a cooling chamber in which to cool the medium to be cooled; a blade mechanism configured to rotate in the cooling chamber to disperse the ice; and a detector configured to detect a locked state of the blade mechanism, wherein a cooling chamber in which to cool the medium to be cooled; a blade mechanism configured to rotate in the cooling chamber to disperse the ice; and a detector configured to detect a locked state of the blade mechanism, wherein the control device is configured to operate the de-icing mechanism when the detector detects the locked state of the blade mechanism, characterized in that the control device is configured to stop the blade mechanism when the detector detects the locked state of the blade mechanism, and in that the ice making system further comprises a temperature sensor for detecting a temperature of the medium to be cooled discharged from the cooling chamber, wherein the control device is configured to stop the de-icing operation when the temperature detected by the temperature sensor for detecting a temperature of the medium to be cooled discharged from the cooling chamber exceeds a predetermined temperature.