Authorities in a city in the Chinese region of Inner Mongolia issued a warning after a patient who had bubonic plague died of multiple organ failure, state media reported.
Cases of plague are not uncommon in China, although outbreaks have become increasingly rare.
From 2009 to 2018, China reported 26 cases and 11 deaths.
The patient was confirmed to have bubonic plague, the People's Daily reported, citing an announcement from the health committee of the Bayan Nur city.
The bubonic plague, known as the "Black Death" in the Middle Ages, is a highly infectious and often fatal bacterial disease that is spread mostly by rodents.
The committee issued a third-level alert, the second-lowest in a four-level system, effective Friday to the end of 2020 to prevent the spread of the disease, the People's Daily reported.
This marks the second death of a plague patient reported this month in the Inner Mongolia region.
On Thursday, authorities in Baotou city, which is adjacent to Bayan Nur city, reported that a patient with an "intestinal-type plague" died of circulatory system failure.
Bayan Nur authorities have locked down the area where the dead patient lived and quarantined seven close contacts of the patient, who have tested negative for the disease so far and taken preventive medicines.