The Guardian columnist said in a tweet that he and friends were set upon while out celebrating his birthday.
He said: "Six of us left the pub at 3am and were saying our goodbyes 30 metres away, then a group of three or four men left the pub, made a beeline for me, kicked me in the back, threw me on the ground, slamming my head, and kicked me in the skull.
"My friends were punched trying to defend me."
Mr Jones indicated he thought the attack was motivated by far-right ideology.
He added: "Given the far-right attacks I've had in the streets, and generally escalating far-right attacks I've had, I'm in no doubt what this is.
"They spotted me in the pub, waited for us to leave, and then launched their attack when we were away from the pub.
"It was planned, not a random attack."
Labour leader Jeremy Corbyn sent a message of "solidarity" to Mr Jones.
Mr Corbyn said: "Owen believes it was politically motivated, and we know the far right is on the march in our country.
"An attack on a journalist is an attack on free speech and our fundamental values."
Guardian editor Katherine Viner has condemned the attack.
She said on Saturday evening: "At the Guardian we deplore the outrageous attack on Owen Jones that took place late last night.
"Violent assaults on journalists or activists have no place in a democratic society."