Rent increases would be capped at inflation and tenants given standard three-year contracts under Labour plans to stop tenants being "ripped off".
Leader Ed Miliband said his party would also give tenants the right to know what rent their predecessors had paid.
Conservative London mayor Boris Johnson said it was a "disastrous policy" that would reduce housing supply.
Mr Miliband also ruled out any post-election "deals" between his party and the SNP to get into power.
Speaking on the BBC's Andrew Marr show, the Labour leader said he could win the election in Scotland and said there would be no "tie-ins" with Nicola Sturgeon's party.
In other election news:
- A clutch of polls suggested there remained little to choose between the Conservatives and Labour
- David Cameron said wages, welfare, housing and childcare would be at the heart of the Conservatives' programme for government in its first 100 days
- Plaid Cymru leader Leanne Wood said she would use the election to push for equal funding between Wales and Scotland
- Nick Clegg said he aimed to remain Lib Dem leader after the election, whatever the circumstances
Housing is a key election battleground, with all the major parties promising hundreds of thousands of new homes to address what campaigners say is a chronic shortage.
Under Labour's plans, landlords would miss out on tax relief if they failed to maintain properties.
Mr Miliband said the policies would help the millions of people priced out of the housing market in recent years and trapped in short-term, often insecure rental agreements.
His party has already announced plans to extend the typical tenancy agreement from a year or less to three years, following a probationary period of six months. Estate agents will also be banned from requiring fees from tenants before they move in.
But the Labour leader said he wanted to do more to stop the estimated 4.5 million households renting privately from being "ripped off".
He is pledging to cap rents during the course of the standard three-year tenancies so they cannot rise by more than the CPI measure of inflation - currently 0% - while allowing flexibility for them to be reduced.
Market rates will still apply at the start of a contract, but tenants will have a legal right to know what the previous tenant paid, which Labour says will put them in a stronger position to negotiate and make substantial rent rises between contracts less likely.
Analysis: Rob Young, Business Presenter, BBC Radio 5 live
In the year to March, rents across Britain went up by an average of 2%. In London, it was a touch higher. With inflation at zero, if Labour's policy were in effect today, rents for the next year would be frozen.
The policy is already proving controversial, particularly with landlords and some economists. Various countries control housing costs to a certain extent. The German parliament recently voted for a tougher policy. New York's rent control law is due to expire soon, and there's a political tussle about its future.
The policy is popular with tenants, but critics say it's led to substandard housing. Britain had controls on rent for more than 20 years until the late 1980s. Labour's plan isn't as restrictive as it was back then.
If it does become law, increasing numbers of people could be affected. Almost half of all young households - aged 25 to 34 - rent privately. That's twice the rate it was a decade ago.
Labour says three-year tenancy agreements should become the norm, with landlords having to give tenants two months' notice to leave and only with "good reason". The rent cap would not apply to those who agreed shorter contracts, such as students or business people needing flexibility.
The party claims rents are, on average, £1,200 higher than they were in 2010, with some tenants in London facing double-digit annual rises.
Asked on the Andrew Marr show about economists who criticise the policy, Mr Miliband said rent controls had been successful in Ireland, since being introduced in 2004. He said Britain was almost alone in having "insecure, one-year tenancies".
David Cowling, BBC political research unit
Some excitement was provoked by several polls published over the past week - from Opinium, Survation and Ashcroft - suggesting four-point Conservative leads.
However, in the same week, ICM registered a five-point drop in Conservative support compared with their poll one week earlier.
I still find it difficult to discern any significant change in the polls that points to an emerging decisive lead by any party.
Labour says "rogue" landlords who did not maintain properties "to basic standards" would lose tax relief enabling them to offset 10% of their annual rental income against falls in the value of furniture and appliances.
Mr Johnson, who joined Mr Miliband on the Marr show, described Labour's rent controls plan as "nonsense" and "a gimmick".
He said: "First of all you'd discourage people from getting into the rental market, you'd discourage the creation of new housing, and all that would happen - fewer houses... [and] at the end of the three years those that remained renting out their properties would jack up the rents even higher."
The Conservatives have placed increased home ownership at the heart of their housing plans, pledging to extend the Help to Buy Scheme to 2020 and extend the Right-to-Buy scheme to up to 1.3 million tenants of housing associations.
Under their plans, housing association tenants would get the same discounts to buy their homes as council tenants currently enjoy.
The Liberal Democrats are promising young people still living with their parents a loan to help pay for a deposit on a rented home of their own.
Deputy Prime Minister Nick Clegg said Labour's proposals sounded "superficially attractive" but would result in "huge hikes" in rent every three years.
The Green Party is also proposing an inflation-linked cap on rent rises.
Speaking ahead of Monday's policy launch, party leader Natalie Bennett said: "Keeping rent rises in line with inflation will reduce poverty and allow tenants a better standard of living."
Roger Harding, of housing charity Shelter, told BBC News a move to limit rent rises to inflation was "very welcome", but Alex Hilton, of tenants campaigning group Generation Rent, said the policy would not reduce anyone's rent and warned rates would "just catch up" between three-year tenancies.
The Association of Residential Letting Agents said flexible tenancies were "what makes the sector work", and the CBI warned against "overburdening" landlords.