Kathy Valentine (born Kathryn Valentine, 7January 1959, Austin, Texas, USA) is the American bass guitarist known for the all-girl New Wave / punk / pop band, The Go-Go's which included Belinda Carlisle, Jane Wiedlin and Charlotte Caffey .
She began playing at age 16 in her hometown of Austin, and joined a fledgling Girlschool in London, England in 1975. In 1978, Valentine relocated to Los Angeles, California and co-founded The Textones with Carla Olson. She joined the Go-Go's on New Year's Eve 1980, as a substitute for an ailing bassist, but was asked to remain as a permanent member shortly thereafter. She wrote "Can't Stop the World" on the Go-Go's début album, and co-wrote the hit singles, "Vacation" and "Head Over Heels", which appeared on subsequent releases. After the Go-Go's disbanded, Valentine played guitar in the World's Cutest Killers with former Girlschool guitarist Kelly Johnson, The BlueBonnets and The Delphines.
In 2005, she released a solo recording, Light Years, that she co-produced, wrote, arranged and performed the guitar and vocal tracks. She now resides in her hometown of Austin with her husband and young daughter. Valentine performs regularly with the Go-Go's, the Impossible, and a new line-up of BlueBonnets.