Giulio Regeni, who was found dead earlier this month, also had seven broken ribs and had suffered a brain haemorrhage, Reuters reported, citing a senior source at Egypt's forensics authority.
The signs of electrocution were found on the 28-year-old's genital area.
The authority gave its final forensic report to prosecutors on Saturday, although the details will not be made officially known while the investigation is ongoing.
The autopsy details come after Egypt's government dismissed accusations that security forces were behind Regeni's murder.
More than 3,000 people attended a private funeral for the doctoral student in his home town of Fiumicello in northeastern Italy on Friday.
Earlier in the day, Prime Minister Matteo Renzi warned Egypt that its friendship was on the line over the probe into his unexplained death.
Renzi said Egypt was cooperating with Rome's demand that Italian investigators be involved in the probe.
Many Italians believe he was abducted and killed by elements of the Egyptian security services.
Meanwhile, nearly 5,000 university lecturers and researchers have signed a letter accusing Egypt of using torture against its own citizens and demanding an independent probe into his death.