Phil Twyford, housing spokesman for the Labour Party, spoke to the crowd at the protest.
He said if people were given security they would reach for opportunity and that was why state housing was started in New Zealand.
"It's how we make sure every child growing up in this country gets a decent start to life and you can't get a decent start to life unless you have a roof over your head," he said.
Mr Twyford said Tauranga was the guinea pig for the Government's plan to sell off state housing stock, but he said many people did not trust organisations to run the state homes in the interest of Tauranga's most vulnerable people.
He said Housing NZ needed to stop being run like a glorified property management agency, and more like a full-service state housing agency committed to putting a decent roof over the people who needed it.
Merivale School principal Jan Tinetti also spoke, saying she grew up in a house owned by the state.
"It gave us security and a way forward as a family," she said.
She said New Zealand had always looked after its most vulnerable people by having a state housing policy.
"That's why I am so concerned about what's happening now [with the sell off of state homes]."
Ms Tinetti said at least 10 per cent of her families in Merivale were homeless.
"They are in a no-win situation. We should be putting more into state housing, not selling it off.
"I am seriously upset about what is happening to our most vulnerable in the city," she said.
Green Party MP Jan Logie said a warm, dry, secure, affordable roof over every person's head was a fundamental of decent society.
"The selloff of state houses is a threat to that."
A spokesman for Finance Minister Bill English said the proposed sale of social houses in Tauranga was to registered Community Housing Providers. Properties would have to stay in social housing unless the Government agreed otherwise, and existing tenants would continue to be housed for the duration of their need.
"Selling properties in this way doesn't reduce the number of social housing places. It just means more of the tenancies will be managed by a non-government housing provider rather than Housing New Zealand.
"The purpose of the Social Housing Reform Programme is to provide better services, including wraparound support, for existing tenants and, in the longer term better, housing options for existing and new tenants."