The present disclosure is directed to providing a battery diagnosing system and method, which updates a diagnosis table of a battery diagnosing apparatus by communication between a central server and the battery diagnosing apparatus, and stores battery state information and a diagnosis code as a backup. According to an aspect of the present disclosure, since the diagnosis table stored in the battery diagnosing apparatus may be updated to a latest state, the battery state may be diagnosed more accurately. In addition, according to an aspect of the present disclosure, since the central server determines whether the diagnosis code generated by the battery diagnosing apparatus is misdiagnosed, the battery state may be diagnosed more accurately and reliably.