The invention relates to a sodium hypochlorite preparation system capable of being controlled and debugged remotely based on an ARM single chip microcomputer and a working method thereof. The sodium hypochlorite preparation system comprises an ARM single chip microcomputer, a first drive circuit, a second drive circuit, an analog signal processing circuit, an electrolysis power supply, a concentrated salt pump, a softened water regulating valve, a softened water flow module, an operation indication module, an electrical conductivity meter, an alarm indication module, a 4G module, an HMI moduleand a wireless data transmission module. The sodium hypochlorite preparation system has a remote diagnosing and debugging function. Warning and alarm can be issued for the key parameters of system operation, so that users can find safety risks early to avoid loss caused by system device aging. Users can be remotely notified of corresponding alarm and handle the alarm, and the parameters of fieldoperation can also be modified and optimized remotely. By using the Internet-of-things technology, manufacturers and users can have a real-time understanding of the field operation situation and dealwith an abnormal situation in time.