Video from the Netflix Is A Joke event appears to show a man charging onto the stage and tackling the comedian before being dragged off by security.
The comedian then said his attacker "was a trans man" during the event at the Hollywood Bowl.
Actor Jamie Foxx joined Chappelle and helped apprehend the alleged attacker before the performance continued.
Video posted on social media appeared to show a man with a badly injured arm being put in an ambulance after the incident.
Comedian Jimmy Carr shared his support for Chappelle after the incident
Twitter/Jimmy Carr
A spokeswoman for the Hollywood Bowl said an investigation has been launched.
She added: “The incident that occurred at the Hollywood Bowl on May 3, 2022, is an active investigation and we are unable to comment further at this time."
It comes after a row in the US over his jokes about transgender people that saw a protest staged by Netflix staff.
In his comedy special, The Closer, the comedian said “gender is a fact” and shared his backing for JK Rowling, who has also attracted criticism for her remarks about the concept of biological sex.
Chappelle previously labelled the backlash to his comments about transgender people as “nonsense”.
Uploading a video to Instagram, he said: “I said what I said and boy, I heard what you said.
“My God, how could I not?
“You say you want a safe working environment at Netflix?
“Well it seems like I’m the only one that can’t go to the office any more.”
Chappelle dismissed suggestions he had been invited to speak to transgender Netflix employees and said he would be happy to meet with them to discuss the issue.
He added: “For the record, and I need you to know this, everyone I know from that community has been nothing but loving and supporting so I don’t know what all this nonsense is about.”
After the incident at the Hollywood Bowl, British comedian Jimmy Carr shared a selfie with Chappelle and described his show as "crazy".
He wrote on Twitter: "The Hollywood Bowl with the legendary Dave Chappelle was crazy.
"Just happy everyone's ok."
It follows Will Smith slapping Chris Rock on stage at the Oscars over a joke the comic made about his wife, Jada Pinkett Smith.
Smith's slap prompted members of the comedy community, including Jack Whitehall and Kathy Griffin, to voice their fears that performers are no longer safe on stage.
Chappelle was attacked on stage in LA
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