Spencer was discussing the violent protests that erupted during the Republican’s inauguration on Friday when a hooded protester blindsided him with a right cross.
The white nationalist was initially dismissive of the incident, writing on Twitter that he “was just physically assaulted twice by antifa. No serious damage. I can take a punch.”
However, he later uploaded a video of himself discussing the incident and describing it as a “really terrible thing”.
In a separate tweet, Spencer wrote that he intended to file a police report on Saturday in the District of Columbia.
A separate video uploaded online reportedly shows the person who punched Spencer being confronted.
Spencer said his attacker had earlier tried to punch him but failed to make full contact.
However, Spencer said in his video post, that the man returned and “punched me basically with all his might”.
“He came out of nowhere, sucker-punched me on my ear. I can’t hear too well out of my right ear at the moment.”
Spencer said that people then attempted to protect him but he was spat at by another person.
“This was three physical assaults – really serious physical assaults - and they occurred in t most cowardly way possible.”
Spencer later Tweeted: “I’m not afraid of a fight but I can’t respect an adversary that throws sucker-punches and targets our women and our mothers.
“Every sucker punch, every tossed egg, every chased white Trump supporters red pills a generation. We are winning without even fighting.”