Changes aimed at forcing the most serious offenders to serve two-thirds of their sentence will be unveiled by Justice Secretary Robert Buckland.
Prisoners convicted of serious violent and sexual offences will no longer be released at the half-way point of their sentence, the minister will announce.
The plan for England and Wales forms part of a review ordered by the PM.
The Conservative conference will focus on law and order on Tuesday, with a speech from Home Secretary Priti Patel.
Ms Patel will say that the Conservative Party will reclaim its place as the party of law and order.
She will say: “To the police service: we back you. And to the criminals, I simply say this: we are coming after you.”
Under the government’s proposed changes, offenders in England and Wales will be released at the two-thirds point in their sentence under strict licence conditions. If offenders break these conditions, they would be returned to prison.
Mr Buckland will say: “We owe it to victims to make this change.
“Punishment and rehabilitation are not opposites. We have to do both. Conservatives believe in offering a second chance to those who are ready to change.”
Peter Clarke, the chief inspector of prisons, recently told the government that the safety of the public is being put at risk by the release of some prisoners.
In his 2018-19 annual report, Mr Clarke said thousands of prisoners who were potentially a “high risk of harm” to the public were being released “without proper assessment”.