Cardcaptor Sakura is the story of 10-year-old Sakura Kinomoto and her growing magical powers. When she first opened a magical book, known as the Clow Book, created by a powerful magician known as Clow Reed, all the magical cards in the book were set free upon the quiet city of Tomoeda. The guardian of the cards, Cerberus, appointed Sakura to re-capture all the runaway cards with the use of a special wand with a bird's head on the end. At first, Sakura doesn't want to be called the official Cardcaptor, but after her best friend Tomoyo Daidouji finds out about her powers, she sticks with it and ends up capturing a good number of the original 70 cards.

All does not stay well, however. A descendant of Clow Reed, Syaoran Li shows up in Tomoeda and demands all the Clow Cards Sakura has captured up to that point. After Syaoran notes that Sakura isn't going to give up easily, the two become rivals, trying to capture a card before the other does. As they capture cards, their animosity grows into a reluctant friendship. The arrival of Syaoran's fiancee, Meiling Li doesn't help matters any, and to make things worse, the final judgement after all the Clow Cards are captured is fast approaching. The last card, the Earthy, is captured, and the Judge, Yue, tests both Syaoran and Sakura to see which of the two is worthy to receive all of the Clow Cards. There is a high price to pay if neither is worthy, though. If neither Syaoran nor Sakura is worthy, then their memories will be wiped and they would have no recollection of the Clow Cards, or even magic. Sakura very nearly fails the test after Syaoran has already failed, but she is saved, and the Clow Cards all belong to her.

In the second story arc, a new danger approaches Tomoeda, and the Clow Cards seem powerless to stop it. All changes however, when Sakura unlocks an entirely new magic she created herself to power the Clow Cards. As all of the Clow Cards are transformed into Sakura Cards, Sakura's magic strengthens. When the cause of all the disturbances reveals himself as the reincarnated Clow Reed, Sakura is put to another test. This time, the stakes are much higher than the Final Judgement. If she fails, the whole world will be put to sleep indefinitely, including her family and friends. With the help of Yue, Cerberus, and Syaoran, Sakura defeats the cause of the disturbances. What she is unaware of, though, is Syaoran's growing feelings towards her. After the Clow Reed reincarnation is defeated, Syaoran confesses his love for Sakura straight to her face, but she doesn't give him a response back. Because the dangers in Tomoeda are over, and all the Clow Cards are now Sakura Cards, Syaoran decides to return to his homeland of Hong Kong. Sakura says goodbye to him at the airport, but her feelings for him are still unknown.

The storyline described above is the storyline as told in the anime series, because it is what most people see before they buy the manga. There are slight changes in the manga, for example, Meiling Li, Syaoran's fiancee, is not in the manga. Also, in the manga, Sakura does give Syaoran an answer for his love, and they meet again in the future. In the anime, people had to wait until the second movie came out before Sakura gave Syaoran a reply. All in all, the anime is not much different from the manga. Both of them are excellent representations of CLAMP's work, and both of them are hits in Japan and North America.