Social housing operator Midland Heart, the Chronicle and Echo can reveal, has given the charity a year to vacate the Oasis House building in Campbell Street.
And NAASH, which is based in the same building and provides accommodation for homeless people, is to be given just three months' notice.
Labour parliamentary candidate Sally Keeble, a Hope Centre patron, said she was outraged at the decision, which will mean the Hope Centre will have to move out of a Â£5.5 million building purpose-built for its needs in 2012.
"Oasis House was provided on the basis that the building would be used by the Hope Centre," said Mrs Keeble.
"That was the whole purpose of Oasis House.
"We lobbied and lobbied the Government to get the money for it and we got the money, so a new purpose-built premises could be built to help tackle homelessness in Northampton.
"Midland Heart should not even be considering evicting them."
Oasis House opened in 2012, providing 48 beds available for the single homeless population, 39 self-contained apartments and a range of homeless support services under one roof.
The Hope Centre runs a day centre there for people in precarious housing situations to get affordable food and housing advice, as well as employment and substance misuse support.
It also runs cooking clubs and in times of low temperature, provides an emergency overnight shelter for rough sleepers.
But its owners Midland Heart say the charities will have to make way so it can increase the amount of accommodation on offer at Oasis House.
A spokeswoman for the company said: "As levels of homelessness continue to rise we have worked with a range of partner organisations to look at ways to not only greatly increase the quality of accommodation available at Oasis House, but to offer more support to help people move on with their lives, find employment and secure a permanent home.
"These services in many cases are what turn people’s lives around and as such we want to ensure that we give residents of Oasis House as much access as possible to this support network.
“To increase the life-changing support available to people living in Oasis House we are making changes.
"Unfortunately, this includes asking Hope Centre to find new premises over the course of the next year. We have advised the Hope Centre of this change at the earliest possible opportunity and will ensure that their staff continue to have access to Oasis House in the future to deliver their important work.”
The Hope Centre is yet to comment.