"Beautiful Days" is the twenty-fourth single from the Japanese boy band Arashi.

It was used as the theme song for the drama Ryūsei no Kizuna, starring Arashi member Kazunari Ninomiya.

The release date and announcement of the single was first confirmed on the online version of the Japanese Yomiuri news on September 21, 2008 and was first heard on the TBS television program Mino Monta no Asa Zuba (みのもんたの朝ズバッ！), a day later, as promotion for Ryūsei no Kizuna.

[1] The single was available for pre-order on online shopping sites on September 27, and the full song was heard for the first time on October 5 on Ninomiya's radio program, Baystorm.

[4] The single debuted at the top spot on the Oricon daily singles chart with total index sales figure of 83,052 (an estimated 145,341 copies sold on the first day), making it the group's 13th straight number one release and their 21st number one overall with a total of 351,860 copies sold in the first week.