The South Gauteng High Court sitting in Palm Ridge handed down the judgement on Monday, according to eNCA.
Donald was arrested in July 2014 after being on the run for several days.
His girlfriend, Dolly Tshabalala, was found dead in their apartment in Jabulani, Soweto. She is believed to have been killed on 29 June 2014.
The high court also found Donald guilty of obstructing justice.
He will be sentenced on 25 November 2015.
Donald will remain behind bars until then as his bail has been revoked, according to the report.
