Dorf drew 300 people to a San Diego hotel for the first incarnation of the annual comic book convention in 1970, the Los Angeles Times reported Friday.
"I just felt that the cartoonists who entertained the popular masses were not getting their fair share of recognition," Dorf said in a 2006 interview.
In August, the 40th annual Comic-Con convention drew more than 125,000 people.
"He brought recognition to creators of comics at a time when no one did. It was considered a children's medium," Comic-Con spokesman David Glanzer said. "He understood the historical value of comics in addition to their artistic value."
Dorf, who died Tuesday in San Diego of complications related to diabetes, donated most of his comic book and memorabilia collection to Ohio State University for the school's pop culture archives.
Dorf is survived by his brother, Michael.