It happened back on August 13 while the event was being hosted at the Doubletree Hotel in Cherry Hill.
Police confirmed Saturday that Busey, 78, of Malibu, California, was charged with two counts of criminal sexual contact, one count of criminal attempt/criminal sexual contact, and one count of harassment.
Police did not identify the suspect as the actor, giving an age and hometown that matched those of the actor, the Associated Press reports. An email was sent to them seeking confirmation of the identification and other details.
The actor was scheduled as a featured guest for all three days of the event.
Authorities have not provided further information on the incident.
Anyone with information is asked to call Cherry Hill Police Department at (856) 432-8834.
Busey has been featured in dozens of films including "Lethal Weapon," "Predator 2," and "The Buddy Holly Story."
It wasn't immediately clear if the suspect had an attorney, and a representative for the actor didn't immediately return a message seeking comment Saturday.
Monster Mania Convention released this statement on the incident:
"Monster-Mania is assisting authorities in their investigation into an alleged incident involving attendees and a celebrity guest at its convention in Cherry Hill, New Jersey last weekend. Immediately upon receiving a complaint from the attendees, the celebrity guest was removed from the convention and instructed not to return. Monster-Mania also encouraged the attendees to contact the police to file a report.
The safety and well-being of all our attendees is of the utmost importance to Monster-Mania, and the company will not tolerate any behavior that could compromise those values. Monster-Mania will continue to assist the authorities in any and every way possible."
The Associated Press contributed to this report.