Joutarou is a fictional character from the Japanese manga JoJo's Bizarre Adventure, and the protagonist of Series 3. He has a recognizable attire of trenchcoat-length school uniform jacket with yellow chains on the collar.

He also wears a trademark hat which, while torn in the back, often seems to blend with his hair. While they are first shown as being completely separate, later publications cause more uncertainty as to where his hat and his hair actually meet. His hat is most likely a Japanese student cap that was normally worn along with the gakuran prior to the 1970s.

He is also known for a quick and short temper. He is the only JoJo to make an appearance in four different series.

Joutarou is Holly Kuujou's son and Joseph Joestar's grandson. When Joutarou first appears, he turned himself in to the police because he believes his Stand is an evil spirit possessing him. To demonstrate, he steals a gun from a prison guard, and tries to shoot himself in the head -- a phantom hand emerges from his arm and catches the bullet, however, only Holly sees the hand. This act naturally earned the widespread fear of the guards and other prisoners towards him.

Joseph comes to Joutarou's aid with Mohammed Avdol. A brief fight ensues due to Joutarou's defiance, getting Avdol involved. After he is released from jail, and learns what his Stand is, Joutarou gets used to Star Platinum, a fierce, muscular, vaguely Aztec-looking spirit with "the precision of a machine" and the ability to destroy virtually anything with a "Fist of the North Star"-like sledgehammer barrage of fists.

In the sixth story arc Stone Ocean, Joutarou becomes an oceanologist, moves to the United States, eventually marries, and his daughter, Jolyne inherits Stand powers. But she also inherits the tradition of adventures that Joutarou tends to get entangled in. She also adopts an outfit style similar to his at one point due to her fascination and respect for her father.

He has a very tough exterior (despite the profile image indicating nothing of the sort), and is even rather rough and delinquent, but he also is very dedicated, intense, and loyal. He is very intelligent, but usually lets his (or Star Platinum's) fists do the talking with the enemy, even though he often has to rely on his wits to deal with stand users' attacks. Joutarou has a perpetual cooler-than-thou, slightly disinterested attitude, although he loves his mother and respects his grandfather. It is not that he is unaware of his own love and/or respect--rather, he thinks anyone can tell his emotions just by looking at him, and probably thinks further effort in portraying how he feels to be a waste of time. In the manga, he's constantly chased by adoring girls, whom he ignores or tries to drive away. He is the main target of Dio, who realizes that Joutarou is his greatest threat.

In part 6, he also shows his protective father side, often taking near fatal blows for Jolyne and throttling her out of harm's way. After he is "revived", Anasui, one of Jolyne's companions who is enthralled by her, asked Joutarou to approve of marrying her. Although he first acted deaf, Joutarou got the picture when he saw her lean against Anasui's chest. Not ready to see his daughter married off right away, he pulled his daughter into his arms, leaving Jolyne clueless to their interactions. His father, a jazz musician, is thought to receive his namesake from Sadao Watanabe, a jazz saxophonist. His father is always on tour and is never seen.

Joutarou is both fierce and gentle, and he shows these traits in various scenes, from the fight with N'Dour to the encounter with D'Arby. One shining example is how he spared Noriaki Kakyoin, instead of destroying him outright, knowing that Kakyoin attacked him unwillingly and was under Dio's influence. The same happened for Polnareff, whom he saved as well. Both became invaluable allies to the end. Unlike with both D'Arby brothers, who got the full brunt of Joutarou's ferocity, he saw in N'Dour blind loyalty rather than greed and evil that was evident with the other enemies. Though still loyal to Dio, N'Dour respected Joutarou for his strength, despite being an enemy, until he breathed his last. In return, Joutarou gave N'Dour a decent burial in the desert.

Joutarou's appearance is interesting in that he exhibits an anime archetype exhibited commonly by "genius" characters by forever staying young through all of his appearances in spite of age.

His catchphrase is "Yare yare daze." It has no direct translation but it is usually translated to the effect of, "Gimme a break." It can also mean "Well well well..." or "all-right all-right...", since "yare yare" commonly translates to "Oh well..." It generally relates of being bored or exasperation. In the official Shonen Jump Advanced manga this is written as "Give me a !@$&*# break..".

In the manga, Joutarou is seen reading a Shounen Jump in his cell, with Shounen Jump being the magazine in which JoJo is published in Japan. These magazines also saved Joutarou from being fatally impaled by Dio's knives.

He is regarded by many as the most charismatic character of the JoJo series.

One of the strongest stands in the JoJo universe; Star Platinum possesses super human senses, strength, stamina, accuracy and speed. It can see for great distances and at great magnifications. As an added bonus, it has a "Star Finger" attack in which it extends its finger to attack. It is similar to Dio's The World stand, and, it turns out, can likewise be used to stop time, but that ability is only revealed in Joutarou's epic battle with Dio Brando when Dio was about to drop a steamroller on him.

The Star card symbolizes, above all, hope. This is very appropriate, since Joutarou is very much the young new hope of the series. Like other physically powerful stands, Star Platinum suffers from a narrow range of activity. It can only be active within a 2-3 meter radius from Joutarou.