Tommy Robinson, who helped set up the English Defence League in Luton in 2009, said he no longer felt that street demonstrations were "productive".
The EDL started in response to a demonstration by Muslim extremists as soldiers marched through Luton.
The group has become infamous for street protests across the country, often resulting in violence as its members clashed with opposing groups such as Unite Against Fascism.
Mr Robinson said: "I recognise that, though street demonstrations have brought us to this point, they are no longer productive.
"I acknowledge the dangers of far-right extremism and the ongoing need to counter Islamist ideology not with violence but with better, democratic ideas.”
Two leaders of the far-right English Defence League are to leave the group, it was claimed today.
Tommy Robinson and Kevin Carroll, who set up the anti-Islamist group in 2009, have decided to leave because they can no longer keep extremist elements at bay, think tank Quilliam said.
The organisation, which calls itself the "world's first counter-extremism think tank", is helping Mr Robinson, who is from Luton, move away from the group and put his energy into countering extremism.
It called for other members of the EDL to follow in his footsteps, and for Islamist extremist leaders to also leave their respective groups.