Song Joong-ki hosted a special event at a children's hospital in Seoul, Tuesday.
The 31-year-old actor volunteered for the Domino's Pizza project.
He handed out slices of pizza to patients, families and hospital staff.
Song shared a warm message of hope and donated $86,000 as a "Hope Sharing Fund" to the hospital.
The actor's close friend, Park Bo-gum, also visited the hospital in December to send a message of hope to patients.
Separately, Song has been donating to the Korea Childhood Leukemia Foundation since 2011.
Song won the Grand Award, Best Couple Award and Asia's Best Couple Award with Song Hye-kyo at the 2016 KBS Drama Awards in December.