"The court ruled that Hamas should be included as a terrorist organisation," said Samir Sabry, one of the lawyers who brought the case the group.
In January, the same court declared the Islamist group's military wing, the Izzedine al-Qassam Brigades, a terrorist organization.
In March last year, Egypt banned Hamas from carrying out any activities on its soil and froze the group's assets.
Authorities in Cairo have accused the group of aiding militants based in the Sinai region wage deadly attacks against Egyptian police and soldiers. Hamas officials have repeatedly denied these charges.
Hamas was founded in the late 1980s. Relations between Cairo and Hamas deteriorated after Egypt's military toppled senior Brotherhood leader and former President Mohammed Morsi in 2013.
Hamas had also been on the European Union's terrorism blacklist since 2001, but was taken off in December 2014 after an EU court ruled the designation was based on media reports rather than solid legal evidence.
Last month the EU said it would appeal the court's decision. Hamas has long contested the terrorist classification.