Thirty men were sentenced to between 10 years to life imprisonment for planning a suicide bombing on a church in Alexandria and other charges, court officials said.
Authorities said at the time of their arrest the defendants embraced the ideas of the Islamic State group and received training abroad and in Egypt.
Twenty defendants who appeared in court, dressed in white prison garb, did not react to the sentences and there was no immediate comment from lawyers representing them. The other 10 are still on the run and were sentenced in absentia.
The attack on the church did not happen. Minority Christians however faced a series of assaults in Alexandria and other parts of Egypt in recent years.
Islamic State claimed responsibility for suicide bombings on churches in Alexandria and Tanta in April 2017 that left 45 people dead.
The defendants were also accused of planning to bomb a liquor store in the Mediterranean city Damietta, joining an illegal group and possessing weapons and explosives.
Eighteen received life terms, 25 years in Egypt, eight 15 years in prison and four were sentenced to 10 years, the head of the Alexandria Criminal Court, convened in Cairo, said.
Egyptian authorities cracked down on Islamist groups since President Abdel Fattah al-Sisi led the 2013 military overthrow of Egypt’s first freely elected president, Mohamed Mursi of the Muslim Brotherhood.