O-Kai Singers is an A Cappella group composed of members from the Atayal, Paiwan, and Han Chinese groups. They perform using unaccompanied vocal harmonization. Less than two months after the group was formed, O-Kai Singers won the championship of the 2004 Taiwan International Chorus Competition hosted by the Taiwan Choral Music Center (TCMC). They have earned the most awards of any Chinese artist, including 55 international awards. O-Kai Singers has been invited to perform with top-notch singing groups such as The Swingle Singers, The Real Group, and The Idea of North, and have performed more than one thousand concerts touring nationally and internationally.

Their first album, O-Kai A Cappella, recorded together with several Grammy Award-winning artists, won them the Jury Award, Best Vocal Group, and Best Aboriginal Album at Taiwan's 24th Golden Melody Awards in 2013, Best Jazz Album at Contemporary A Cappella Recording Awards (CARAs), and 2012 Top 10 Albums at Taiwan Music Man Association. Their second album, Some People Say, released in 2018, won the Best Asian Album of CARAs, Best Chinese Arrangement and Best Recording at Beehive Awards, Best Jazz Vocal Album at CMIC Music Awards, Best Vocal Group at Freshmusic Awards, Gold Medal at Global Music Awards, and was nominated for the Best Vocal Group at the 30th GMA Golden Melody Awards.The third album, Those Days, released in 2023. It was nominated for three major awards, the Best Vocal Group, Best Aboriginal Album,and Album of the Year ,won the Best Vocal Group at Taiwan's 35th Golden Melody Awards.