Amanda Knox and Raffaele Sollecito have been found guilty of the murder of British student Meredith
Kercher after judges in Florence overruled their previous acquittal.
It is the third time American Knox, 26, and Italian national Sollecito, 29, have faced trial over the death, in Perugia in 2007.
Neither defendant was in the courtroom as the verdict was announced, though Sollecito had attended the lengthy hearings.
Members of Miss Kercher's family were there to hear the verdict.
The co-accused were originally found guilty of murder in 2009, and were handed jail terms totalling more than 50 years.
They were cleared nearly two years later - but the appeal court ordered a fresh trial in March last year.
Thursday, after lengthy deliberations, the court heard that both were guilty.
It is unknown whether the duo will appeal the decision, or whether Knox could be extradited from the US to Italy.
Rudy Guede, a drug dealer, is serving a 16-year sentence over the death - though the courts have said he did not act alone.
