The chancellor has come under fire for his proposals which will see the main rate of Class Four NICs increase by two per cent over the next two years.
The rise will affect self-employed people earning profits over £8,060 a year.
Patrick O'Flynn accused the chancellor of hammering the self employed.
It’s a betrayal of White Van Man and also a huge number of women
Critics have hit out at Downing Street for attempting to raid small businesses owners and those working for themselves, a statement echoed by Mr Flynn.
The Eurosceptic argued the move showed the Conservative party “no longer understood enterprise”.
Speaking on BBC News, he said: “It’s a betrayal of White Van Man and also a huge number of women who are building their businesses starting off with self-employment.
“These people don’t get paid holiday, they don’t have a company pension, they don’t get sickness pay and now they’re being hammered by a chancellor who has spent much of his time talking about cutting the tax on big corporations.”
The Ukip MEP said self-employed workers had been "hammered" by the Government
Mr Hammond defended his controversial policy, insisting the current NICs system was unfair to the 85 per cent of people in the country who are employed directly.
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He said self-employed people pay less NICs but still benefit from the same level of public services, such as access to the NHS.
Mr O’Flynn dismissed the statement, as he continued: “There has to be an incentive to get out there and set up your own business.
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Budget 2017: Philip Hammond hailed Britain’s booming Brexit economy today as he delivered his first Budget of the year
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Mr Hammond says he is 'building the foundations of a stronger, fairer, more global Britain'
“I’ve never set up my own business, I’ve never been self-employed, I’ve always been on PAYE but I do admire the people who have the gumption to make a go of it who have no guaranteed income.
“They may have thought in the past that the Conservative Party always say they are the party of small businesses, but it didn’t sound like it today.”
The chancellor has predicted the increase in NICs for self-employed workers would raise £145m for the public purse each year by 2021.
Mr Hammond says on average the extra tax would equate to 60p per week for a self-employed person in the UK.