Osamu Tezuka's Star System (手塚漫画のキャラクター一覧, Tedzuka Manga no Kyarakutā Ichiran; lit. The Tezuka Manga Character List) is the name given to the recurring characters in manga created by manga artist Osamu Tezuka. Throughout his career, Tezuka frequently re-used the same character designs or names in different roles across his series; for example, the character Shunsaku Ban appears as a detective in Metropolis and as Astro Boy's teacher in Astro Boy. The name alludes to the Hollywood practice of the star system, and can be seen as analogous to film directors who work with the same actors across multiple films; Tezuka joked about how much his characters were paid, and occasionally based them on famous western actors.

Akira Asagumo is the grandson of the scientist Dr. Asagumo. He gets his super human powers from the chemical called "Big X", which gives him the ability that makes him grow and expand without limits. He appeared in Shōnen Bool from 1963 to 1966.

Atom (Japanese: アトム, Hepburn: Atomu) is a principal "actor". He is shown in the famous manga and assorted versions of the anime as a child robot, usually wearing shorts (which are actually part of his body), identified by his trademark, two pointy "cowlicks" on the front and back of his head. In the manga, his good nature and incorruptible heart, combined with an array of powers, put him on a quest to protect robots and humans from villainous conquerors and alien invaders. He made other appearances in other manga including Black Jack's, in which he plays a major role in at least one story (volume 22 of the English manga release by Dark Horse of Astro Boy) and in the anime Undersea Super Train: Marine Express, in which he is called "Adam". Astro resembles the wooden boy Pinocchio.

Black Jack (ブラック・ジャック, Burakku Jakku) is a cold-natured, eerie, yet kindhearted and ingenious surgeon is one of Tezuka's dearest creations, despite the fact that in the present day he receives little credit compared to his rival Astro Boy. Black Jack is, according to Tezuka, his alter ego. Black Jack refuses to get a medical license, due to the corruption within medicine practices, and may run into the legal forces while doing operations (in the 2006 TV anime Black Jack finally gets his license). Despite his outlaw status, he is considered a miracle worker with his incomparable surgical technique and power of diagnostic analysis. His operations are generally over 10 million yen, but he more frequently helps the unfortunate for free or a token payment. He is sometimes accompanied by his short-tempered adopted daughter/assistant, Pinoko and can be recognized by a large cape, loose trench coat, and blue, black or red string tie (depending on the media) with black and white hair, dark eyes, and a graft of dark skin across the upper left of his face. Having learned wit playing with darts as a boy, is a skilled marksman as well as well-trained in martial arts. A statue of Black Jack stands in the Osamu Tezuka Museum beneath a skylight.

Bokko, Pukko and Nokko are a trio of three intergalactic patrollers known as the Amazing 3. They came to Earth to research and destroy it if necessary. They appeared in Weekly Shōnen Sunday from May 1965 to May 1966.

Don Dracula (ドン・ドラキュラ, Don Dorakyura) is a comical vampire who moved from Transylvania to Japan and has a hard time adjusting to the new place. In the animated film Marine Express and the video game Astro Boy: Omega Factor, Don Dracula is a villain who works for Sharaku.

Garon (ガロン) is a giant robot sent by aliens as a test for Earth's inhabitants. His original comic, Majin Garon, ran in Boukenoh (Japanese: 冒険王, lit. 'Adventure King') from July 1959 until July 1962. He is the final boss of the video game Astro Boy: Omega Factor and the secret treasure of Mu.

Ham Egg (ハム・エッグ, Hamu Eggu), also known as Cachatore, Hammond Eggs, Hamegg, or Simon Sakely (in Jungle Emperor Leo) is a villain with a round head, a thin moustache, a wide grin, curly hair and sometimes a top hat. His name is an obvious play on the words "ham and eggs".