DK X Seungkwan (; also known as DxS) is a sub-unit of South Korean boy band Seventeen, consisting of vocal team members DK and Seungkwan. Formed by Pledis Entertainment in 2026, the duo debuted on January 12 with the extended play (EP) Serenade.
On November 6, 2025, Pledis Entertainment announced that DK and Seungkwan of Seventeen would debut as a new sub-unit, making it the fifth sub-unit of the band. The duo is also a part of the band's another sub-unit BSS. In December, the pair released a cover of Bruno Mars and Lady Gaga's "Die with a Smile", and on December 17, the trailer for their debut extended play (EP) was released, revealing its title and release date, and on December 23, official photos for their album was released. The duo released their first extended play, Serenade, on January 12, 2026. In support of the EP, the pair performed a showcase on January 18 at the CG Art Hall in Seoul.