Winehouse Family -- Amy Was NOT On Drugs When She Died

Amy Winehouse's family claims toxicology tests prove Amy was not on any sort of illegal drugs at the time of her death ... but she had been drinking.

According to the family, officials have not determined if the booze played a role in the singer's death.

The family did not mention if prescription drugs were detected in the toxicology report.

The statement comes as a shock to just about everyone on the planet ... since Amy struggled with a MAJOR substance abuse problem for years.

TMZ spoke with a rep from Scotland Yard ... who told us the law enforcement agency has not yet received a copy of the toxicology results from the coroner.

Winehouse died in her London apartment on July 23.

7:43 AM: A rep for the family released a statement saying, "Toxicology results returned to the Winehouse family by authorities have confirmed that there were no illegal substances in Amy's system at the time of her death."

The statement continues, "Results indicate that alcohol was present but it cannot be determined as yet if it played a role in her death."

"The family would like to thank the police and coroner for their continuing thorough investigations and for keeping them informed throughout the process. They await the outcome of the inquest in October."