Stefano Alessandroni is an Italian actor and voice actor known for his work in theatre, television, and film, with a substantial body of work in dubbing for live-action and animated productions. Born in Rimini, he moved to Rome at age nineteen to pursue an acting career. His early professional breakthrough came in theatre, where he performed in numerous productions with prestigious Italian companies and under acclaimed directors such as Luca Ronconi and Gigi Proietti. He has cited his extensive stage experience as a fundamental part of his artistic development. Alessandroni transitioned to voice acting around 2010, drawn to it as a complementary skill for an actor's completeness.

In the realm of anime and animated features, Alessandroni has lent his voice to a variety of characters. He is the voice of En, a powerful and central character in the series Dorohedoro. He voices the character Ohfan in the fantasy film The Deer King. His credits also include the role of Shu Izumi in the film The Relative Worlds and the character Il Gladiatore in the series Super Crooks. Alessandroni provided the voice for Halu-Elu Dolu-do in the anime film trilogy Godzilla: Planet of the Monsters, Godzilla: City on the Edge of Battle, and Godzilla: The Planet Eater. His other anime voice work includes roles in Frieren: Beyond Journey's End, BEASTARS, Ranma ½, and the live-action adaptation of One Piece, among many others.

Beyond animation, Alessandroni's extensive dubbing career includes voicing actors in prominent live-action films and series. Some of his noted dubbing roles include the guard in The Hangover, a character in The Dark Knight, and the protagonist in the television series Escape at Dannemora. He has also voiced characters in films such as Bumblebee and the Italian versions of animated features like Cars 2 and Fantastic Mr. Fox.