Black cab rapist John Worboys is lined up for two bodyguards and protection costing £300,000 a year.
Worboys, 60, could be released after a hearing later in March and probation service officials are assuming he will be freed - despite public outrage.
Worboys, Britain's most prolific sex offender, is thought to have attacked more than 100 women in total using a rape kit of spiked champagne.
One of his victims told The Mirror: "Worboys' release is a betrayal and an insult to his victims, who all suffered horrendous attacks.
"We still live with what he has done to us but the government will pay hundreds of thousands to protect him. How is that justice?"
Worboys has two properties – one in London and one in Poole, Dorset – but probation chiefs have had to find him a place in a specialist bail hostel.
A source said the Probation Service plan is to place Worboys outside London, where many of his victims live, have him live under strict conditions and with guards to protect his safety.
The source added: "The threat to his safety is so real that two members of staff will monitor him 24/7. This will come at great expense and could cost up to £300,000 a year.
"He will also be the subject of the strictest licence conditions."