Thank U is the debut Japanese studio album by the South Korean rock band CNBLUE. The album was released on March 20, 2010 in Japan and the majority of the songs were sung in English with the exception of "voice" and "a.ri.ga.tou." Several of the songs on this album were later released in Korean in the band's debut Korean album, First Step. This album is the first of the two indie albums CNBlue released before signing with Warner Music Japan for their major Japanese debut on October 19, 2011. The album sold over 10,237 copies.