|Game series||Tekken series|
|First appearance||Tekken 3|
|Birth date:||10 July 1999|
Even at a very young age, Ling Xiaoyu loved amusement parks. Also she was tutored in martial arts by Wang Jinrei from a young age. He believed that if she were more serious, she could achieve true greatness, but became frustrated by her careless attitude.
While vacationing in Hong Kong with her family, she noticed a yacht bearing the name: “Mishima Zaibatsu”. Knowing that the Mishima Zaibatsu was rich and powerful, she decided to seek out Heihachi Mishima and make her dream a reality. Abandoning her family, Xiaoyu stowed away on the ship.
The ship’s security soon discovered her and informed Heihachi of her presence. By the time that Heihachi arrived on the scene, all of the Tekkenshu—Heihachi’s personal security force—that were aboard the ship had been beaten into unconsciousness and strewn about the deck. It looked as if the ship had been hit by a hurricane.
Amidst the chaos, Heihachi found Xiaoyu. She threatened to beat him up if he did not accept her challenge. Amused by her juvenile antics, Heihachi roared with laughter and promised to build her theme park if she won his tournament. She enrolls at the Mishima Polytechnical School, and this is where she first meets both Jin Kazama and Miharu Hirano. Bringing along her old school's trained panda (aptly named "Panda"), Heihachi teaches her to fight, much like he had taught Kuma, so that Xiaoyu would have a bodyguard. This inspired Xiaoyu to see Heihachi as something of a grandfather toward her.
After the King of Iron Fist Tournament 3, Xiaoyu continued to live, study, and train as a ward of the Mishima Zaibatsu, but her life became boring and mundane, lacking any particular goals.
Two years later, Xiaoyu was delivered an anonymous e-mail admonishing her not to trust Heihachi. The anonymous individual warned her that Heihachi posed an immediate danger to her life. At this time, Xiaoyu was a junior at the Mishima Polytechnical School and had become sick of her daily routines, but receiving this mysterious e-mail rejuvenated Xiaoyu’s passionate spirit.
Xiaoyu replied to the e-mail dozens of times. Although the sender never contacted her again, Xiaoyu became convinced that Jin, who had been missing since the previous Tekken tournament, had sent it to her.
Around this same time, Heihachi announced the King of the Iron Fist Tournament 4. Hoping to reconnect with Jin and unmask the Mishima Zaibatsu’s evil deeds, Xiaoyu decided to enter the tournament.
At the end of the previous tournament, Xiaoyu is rescued from the evil plans of Heihachi Mishima by Yoshimitsu, who then tells her about the tragic history of the Mishima family. Xiaoyu starts to believe that the root of all misfortune surrounding Jin and the Mishima family was Heihachi pitching Kazuya off the edge of a cliff when he was five years old.
At this point, Xiaoyu believes it is her personal mission to save the tragic Mishima family. She wished that there were some way to turn back time and fix the past. Her prayers were answered when she heard an unnamed scientist boast that if he had the money, he could build a time machine.
To obtain the money to fund the invention, Xiaoyu enters The King of the Iron Fist Tournament 5 to win the prize money.
Ling Xiaoyu breathed a sigh of relief when she heard Heihachi had not truly died. However, as head of the Mishima Zaibatsu, Jin Kazama aims to take Heihachi’s life. Xiaoyu was going to try and stop Jin herself, but the Zaibatsu pushed towards militarization, making it difficult to approach Jin.
The Mishima Zaibatsu’s declaration of war drew hostility from around the globe. When the King of Iron Fist Tournament 6 is announced, Ling Xiaoyu enters in the hope that she can save Jin’s soul from evil.