Under the bill, a tenant would be able to seek a review of an increase by Tasmania's Residential Tenancy Commissioner if it was above CPI.

Tenants Union of Tasmania principle solicitor Ben Bartl said rents across the state have increased on average by 37 per cent over five years.

"The average renter is in housing stress, having to spend a minimum 30 per cent of their income keeping a roof over their head," he said.

"At the same time, Tasmania currently has the weakest rent control measures in Australia.

"Rents are rising to unsustainable levels for many Tasmanians and any bill that seeks to control rent levels is welcomed."

IN OTHER NEWS:

Mr Bartl said two tenants had contacted the union this week about rent rises of $130 and $165 per week.

Property Council of Australia state executive director Rebecca Ellston said linking rent increases to CPI would not address supply and demand issues with housing.

"Linking rent increases to CPI will be a brake on housing investment which will contribute to a worsening of the current crisis, not an improvement," she said.