A children's hospital and a centre for day surgery patients have been proposed as part of a five-year plan from a health trust.
The shake-up would also include a newly-designed accident and emergency department at Leicester Royal Infirmary.
Detailed plans have still to be drawn up, but University Hospitals of Leicester NHS Trust estimated they would cost about £250 million over the next five years.
It is the first major scheme put forward for the future of Leicester Royal Infirmary, Leicester General and Glenfield hospitals since the Pathway project, in 2007, which was scrapped when estimated costs rose to £921 million.
Jim Birrell, interim chief executive at the trust since July, said: "There wasn't much of a strategy when I got here and the money for this vision will have to be found over the next five years."
He described Leicester Royal Infirmary as "looking increasingly tired" and said: "We need to spend £20 million-plus to make it better.
"Car parking is disastrous and people can't easily find where to go.
"Some of the facilities are just awful and when people come into our emergency department we cannot treat them as quickly as we would like.
"Our clinical standards are high but this work needs go ahead to improve the quality of care."
Plans for the infirmary include creating a children's hospital on the Sandringham building site and a new-look accident and emergency department.
Glenfield Hospital would become the centre for specialist services such as cardiology, stroke care and renal services.
The General would have a day surgery centre and outpatient facilities, plus a diabetes centre of excellence.
Mr Birrell said: "The General is a really important site and it won't be a neglected part of the organisation."
But he warned the plans were dependent on the trust gaining foundation status.
This would give managers more independence in deciding how and where money was spent.
Mr Birrell said: "As a foundation, we will be able to borrow the money for this work.
"It is still going to be tight. Precise numbers have still to be worked out and we need support from GPs and other health organisations.
"We have tried to come up with a scheme which is not pie in the sky.
"It is important for the people of Leicestershire that we don't present them with something we can't do.
"It may be that the plans take longer than five years, but people in the area deserve a first class set of hospitals."
Plans are being shown to MPs, campaigners and councillors.
It is expected that early next year patients will have a chance to comment on them as part of public consultation on the application by Leicester's hospitals to become a foundation trust.
Jon Ashworth, Labour MP for Leicester South, said: "These are important plans and show that the hospitals are going in the right direction."
Ballu Patel, chairman of the Leicester Mercury Patients' Panel, which has seen the scheme, said: "It is good to see some thought has been put into restructuring of the hospitals.
"However, in the interim we need to make sure that areas which may be struggling, such as dealing with winter pressures, are equally addressed."