Note: This game is also titled Naruto Shippuuden: Saikyou Ninja Daikesshuu 5.
Press Down, Up, Down, Up, Left(2) to display the password menu. Then, enter one of the following passwords to unlock the corresponding character:
Enter "Sand Box" as a password to unlock Gaara.
Enter "Sharingan Demon" as a password to unlock Itachi.
Enter "Youth" as a password to unlock Might Guy.
Enter "Strong Wind" as a password to unlock Temari.
Enter "Ninja Tools" as a password to unlock TenTen.
Successfully complete the indicated task to unlock the corresponding character for purchase at the listed shop: