The National Council for Human Rights, the country's official rights watchdog, made the remarks in an annual report.
"The human rights situation in the country has not changed in spite of the adoption of the new constitution two years ago," the report said.
It added that the council had raised 266 cases of enforced disappearances with the interior ministry, of whom 27 were since revealed to have been released while 143 remained in pretrial detention.
The cases were documented between April 2015 and the end of March this year.
Also Read
Rights groups had accused Egypt of extensive abuses that spiked after the military overthrew Islamist president Mohamed Morsi in 2013, unleashing a bloody crackdown on his followers.
The report also criticised the state for failing to pass effective legislation to curb torture, although it acknowledged that President Abdel Fattah al-Sisi had tried to end the abuses.
The report noted that suspicions that security services had abducted Italian student Giulio Regeni, whose mutilated body was found on the side of a road, had been boosted by "the continuation of the phenomenon of torture" in Egypt.
The report did not shed any light on Regeni's disappearance, which created a diplomatic rift between Egypt and Italy, a close ally. Police have denied involvement.
The council said it had received 296 complaints during 2015.
"Many of the complaints are related to abuses they are subject to in prisons and other detention facilities, most notably torture and other harsh and degrading treatment," the council said.
Meanwhile, pretrial detention has become "a punishment in itself".
Initial detention centres are estimated to hold more than 300 percent of their capacity, the report said.
Detainees "take turns sleeping because of lack of space".