Herbert Paul Gilley (October 1, 1929 – June 16, 1957) was a country music lyricist and promoter from Kentucky. In his lifetime, he was little known as a songwriter, but decades after his death by drowning at age 27, he was identified more widely as likely having written the lyrics to a dozen famous songs, including two that were hits for Hank Williams: "Cold, Cold Heart" and "I'm So Lonesome I Could Cry". He may have also written "I Overlooked an Orchid", which was a number-one country hit in 1974 for Mickey Gilley (no relation). Other songs that have been attributed to Gilley include "If Teardrops Were Pennies", "Don't Let the Stars Get in Your Eyes", and "Crazy Arms".
Gilley's contributions to songwriting are not widely known; he is not listed in the Oxford New Encyclopedia of Country Music published by the Country Music Hall of Fame and Museum, nor in Barry McCloud's Definitive Country encyclopedia. However, his hometown declared a Paul Gilley Day in 2012, and Kentucky historian W. Lynn Nickell has written a biography, Paul Gilley: The Ghost Writer in the Sky.