The Liberal Democrat, who was out campaigning in Launceston, Cornwall, when a former Ukip candidate opposed his Remainer policies.
Mr Farron, on Wednesday, had already claimed he would fund a £7billion injection into education funds by maintaining partial membership of the European Union.
During a visit to Lewannick Primary School, the Lib Dem leader was approached by Alan Haithwaite, former Ukip candidate for Truro and St Austell in the 1997 General Election.
Mr Haithwaite told Mr Farron the area had voted Leave and the issue of Britain’s future inside the EU had already been decided.