Ryan Cayabyab (born Raymundo Cipriano Pujante Cayabyab on May 4, 1954 in Manila, Philippines but known as Mr. C) is a Filipino musician and was the Executive and Artistic Director of the defunct San Miguel Foundation for the Performing Arts. He was also a resident judge for the only season of Philippine Idol in 2006.
His works range from commissioned full-length ballets, theater musicals, choral pieces, a Mass set to unaccompanied chorus, and orchestral pieces, to commercial recordings of popular music, film scores and television specials.