Cho Chang was born c. 1979. She entered Hogwarts in 1990 and was sorted into Ravenclaw. In 1993, she joined the Ravenclaw Quidditch team as their Seeker. Cho is very popular, and often has a group of friends around her.

Harry saw Cho for the first time when his Gryffindor team was about to play a match with Ravenclaw. His reaction, which surprised him a little, was that she was very pretty. As that school year went by, he developed a crush on her. At the start of the 1994-95 school year, when the Triwizard Tournament was announced, he imagined himself winning and seeing her face shining with admiration for him. Cho seemed somewhat sensitive to his feelings, or perhaps she is just a particularly kind person, because she didn't join in when the rest of the students treated Harry badly after he became a school champion.

When it was revealed that he was expected to ask a girl to the Yule Ball, he spent days trying to work up the courage to ask Cho to go with him. But when he finally did ask her, she had to turn him down because she's already said yes to Cedric Diggory. Even in this awkward situation, though, Cho was very kind to Harry. Clearly, even if she doesn't have romantic feelings for him, she considers Harry to be a friend.

Cho and Cedric became a couple after the Yule Ball, much to Harry's chagrin, and they walked around the school hand in hand. Harry's jealousy kept him from acting on the advice Cedric gave him about the golden egg until it was almost too late. In the second task, she served as hostage for Cedric to rescue, spending several hours deep under the lake in a bewitched sleep.