Officials said assistant deputy coroner Suzanne Greenaway, who oversaw the inquest, lacked the proper credentials. She had been appointed by her husband, Andrew Reid. Both have since resigned.
Winehouse was found dead in her London home in July 2011. Officials originally ruled the 27-year-old died from accidental alcohol poisoning.
A new hearing has been set for Jan. 8. It appears unlikely that a second inquest would produce a different conclusion. A Winehouse family spokesman says the family did not request the new hearing.
The Associated Press contributed to this report.