The Labor Party said pensioners and working Australians will be most disadvantaged by this year's Budget proposals.
Opposition Leader Bill Shorten said the Liberal Government's budget is "unfair" and favours big business.
In a series of Tweets, Shorten said the 2018-19 Budget fails the fairness test and gives big business and the banks an $80 billion tax handout, making every day Australians pay for it with savage cuts.
"All the worst of Turnbull's cuts are still in this budget - the cuts to schools, the cuts to hospitals, and the cuts to pensioners.
"Every budget is about choices. Yet again, Turnbull has chosen the top end of town - and he's making you pay for it," he said.
Shadow Minister for Finance Jim Chalmers reiterated Shorten's sentiments, adding any budget that gives "a handout to big business but hurts pensioners is a bad budget."
Chalmers said the proposals fail the fairness test on pensioners. Turnbull is cutting the energy supplement, costing pensioners $14 a fortnight and forcing people to keep working until they are 70, he added.
"We know middle class and working class people are struggling with the cost of living - this is overdue relief, but it doesn't make up for Turnbull's cost of living increases and cuts to penalty rates."
Chalmers said funding just 14,000 new in-home aged care packages over four years is a "hoax" as funding cut from residential aged care will pay for it.
"There are still 100,000 people on Turnbull's waiting list for in-home care. It's a particularly cruel hoax after promising older Australians they would address the crisis."
In response to simplifying the personal tax system that proposes abolishing the 37% tax bracket entirely in 2024-25, Shadow Treasurer Chris Bowen described it as "ridiculous" to wait for a tax cut that long.
Bowen told the ABC's Leigh Sales in an interview that "you will have to re-elect Malcolm Turnbull twice to get that tax relief." It's a proposal, Bowen said, that is "completely reckless."
In his speech, Morrison said Australians earning more than $41,000 will only pay 32.5 cents in the dollar all the way up to the top marginal tax rate threshold, which will be adjusted to $200,000, to account for inflation and expected wage movements over the next seven years.
Under the Turnbull Government's personal tax plan, most working Australians earning above $41,000 are likely to never face a higher marginal tax rate through their entire working life, Morrison said.
"The plan is affordable and funded. The total revenue impact on the Budget and forward estimates is $13.4 billion. The overwhelming majority of this cost commences in 2019-20, the same year the Budget is forecast to return to balance."
Morrison also firmly opposed the Labor Party's proposed dividend imputation reforms, calling it an "unfair tax grabs on retirees and pensioners."