The National Women's Council of Ireland said the Budget was bad for women, children and the economy.
The council said many low paid women will be forced to decide if they can afford to stay in the workforce because of changes announced by Minister for Finance Brian Lenihan.
"It is a cod to say that those on the reduced minimum wage will be kept out of the tax net," the council said. "Over 60 per cent of those on the minimum wage are women, so they will bear the brunt of a further cut which will have no impact on overall competitiveness or unemployment."
It said reducing child benefit would mean many families might struggle to cover childcare costs.
It said that almost 100,000 here already live in poverty and that the "shameful figure will rise because there is no protective measure for those on low incomes or welfare".
The Society of Saint Vincent de Paul warned that people in receipt of social welfare and lower pay would experience serious difficulties as a result of the Budget.
The charity said the Budget was a purely economic exercise with little concern for social matters. "The impact on people on social welfare and low pay is much greater than on higher earners and will only lead to increased poverty," it said.
The society said it was unconvinced that the poorest and most vulnerable in society had been adequately protected. It was bracing itself for a surge in calls from concerned clients.
The Family Resource Centre National Forum said pressure on families would increase significantly as a result of the Budget.
"Many of the families that we meet everyday are dependent on social welfare, child benefit and fuel allowance, all of which were reduced in today's budget," it said.