After graduating, Aoyama worked as an assistant director to Swiss film director Daniel Schmid, Japanese director Kiyoshi Kurosawa and Icelandic director Fridrik Thor Fridriksson.[5] He made his directorial debut with the V-Cinema production It's Not in the Textbook! in 1995.[6]
Aoyama's literary output includes his 2001 novelization of Eureka, which won the Yukio Mishima Prize,[12] as well as the novel Hotel Chronicles, which was nominated for the Noma Literary Prize in 2005.[13] He has also contributed as a critic to Cahiers du Cinéma Japon[14] and Esquire Japan.[15]
As of 2012, he became a professor in the Department of Moving Images and Performing Arts at Tama Art University.[16]
Mark Schilling of The Japan Times described Aoyama as "A smart, dedicated cinephile who works his influences into his films while experimenting with various genres".[18]
Aoyama stated that the origin of the desire to continue the story in "Kitakyushu Saga" is François Truffaut, a French film director who used the same character (Antoine Doinel) in some of his films.[19]
Aoyama listed F. W. Murnau's Faust and Nicholas Ray's Johnny Guitar as two of the Greatest Films of All Time in 2012. Regarding Faust he said, "I always want to remember that movies are made out of the joy of the replica. The fascination of movies is not their realism, but how to enjoy the 'real'. In that sense, I always have Faust in my mind as I face a movie, make a movie, and talk about a movie." Regarding Johnny Guitar he said, "Johnny Guitar is the only movie that I‘d like to remake someday, although I know that it’s impossible. It’s probably closest to the worst nightmare I can have. I know for sure that my desire to remake this movie comes from my warped thought that I want to remake my own nightmare."[20]