The leader of the UK Independence Party has been reported to Brussels authorities after his Europe of Freedom and Direct Democracy group (EFDD), which champions the 'Say No To EU' campaign, reportedly received £4.7million from the Parliament in the past three years to fund its activities.
Farage, 51, was reported to the president of the European Parliament by Labour MP, Wes Streeting.
Mr Streeting wrote to EU president, Martin Schulz, after he found out that some of the money was being used for Farage's anti-EU tour, the Mail Online reports.
The 32-year-old tweeted: "I've asked the President of the European Parliament to investigate Nigel Farage's use of taxpayer £ for anti-EU tour."
The Ukip leader is currently touring the UK, speaking at theatres, halls and stadiums in a bid to persuade people to vote to leave the EU.
Mr Streeting said: "Nigel Farage has a catalogue of questions to answer about whether he is spending taxpayers’ money on his campaign and breaching European Parliament rules.
"Mr Farage has already criticised David Cameron over the use of public funds in the referendum campaign, so any suggestion that Ukip has bankrolled his anti-EU tour with European taxpayers’ money must be thoroughly investigated by the Parliament’s authorities.
"Perhaps Nigel Farage will now rule out using any further EFDD funding for his anti-EU campaign?"
Farage has been an outspoken opponent of institutions, such as universities, pushing a pro-EU agenda.
At the weekend, the Eurosceptic criticised the UK's universities for backing Britain's membership of the European Union.
An EFDD spokesman said: "The EU and political groups spend billions on pro-EU propaganda. They can't complain when elected MEPs facilitate public knowledge and debate on how the EU 'works'.
"There no is such thing as EU money. In the UK it comes from mainly Eurosceptic taxpayers who deserve to be represented and have their voices heard. The slavishly pro-EU and pro-TTIP Labour Party may disagree. "