Almost 30 people earning incomes over €1 million have paid little or no tax, according to the latest figures released by the Minister for Finance.
A further 67 people earning between €500,000 and €1 million paid tax at the marginal rate, while 10 earning that amount paid no tax at all.
The figures cover the years 2000/2001, the "short" tax year in 2001 and 2002.
They show that 437 people earned €1 million or more in 2002, an increase of 33 from 2000.
In 2002, one of the super-earners paid no tax at all, and five paid tax at the marginal rate of 20 per cent.
In the previous short transitional tax year from April to December 2001, two millionaire earners had no tax liability, while 11 paid at the marginal rate.
In 2000/2001, the figures show that 10 of the super-earners paid tax at the marginal rate, which was 22 per cent in that tax year.
The figures, compiled by the Revenue Commissioners, were released by Finance Minister Brian Cowen in response to a parliamentary question from Labour's finance spokeswoman Joan Burton.
Deductions from taxable income include "allowances such as capital allowances, losses, allowable expenses and retirement annuities", said Mr Cowen. "In some cases, these will reduce the taxable income to nil."
A review of some tax relief schemes is under way, and Ms Burton said the figures showed that "the study has to address fundamental inequities in the tax system".
The figures also showed that of the high earners on incomes of between €500,000 and €1 million, five people paid no tax in 2000/2001, while 26 paid 22 per cent tax. In the next year five people paid no tax, while 30 had a marginal rate tax bill.
In 2002, some 11 people earning between €500,000 and €1 million paid at the marginal rate.
Ms Burton said "significant numbers of the ultra well-off are continuing either to pay no tax or low tax despite high incomes. It is an equality issue in the tax system."
Mr Cowen said he was "informed by the Revenue Commissioners that it is not possible at present to identify the number of Irish domiciled persons claiming to be non-resident for tax purposes". However some audits were under way "into claims to non-residence as part of the risk-based programmes operated by Revenue".