Lou Gramm (born May 2, 1950 in Rochester, New York) is an American rock music vocalist and songwriter, best known as the lead vocalist for the rock band Foreigner, but who also had a successful solo career.

Gramm was the drummer with the band Black Sheep when the band, and their 1975 album Encouraging Words were noticed by Mick Jones who was then looking for a lead vocalist for a new band he was forming. Ultimately Gramm joined the band, and with Foreigner became one of the most successful rock vocalists of the late 1970s until the mid 1980s.

He sang lead vocals on all of their hits including the rock songs "Feels Like The First Time", "Cold As Ice", "Hot Blooded", "Urgent", "Double Vision", "Dirty White Boy" and "Say You Will". The band achieved two of their biggest hits with the ballads "Waiting For A Girl Like You" which spent 10 weeks at number 2 on the American singles charts, and "I Want to Know What Love Is" which was a number 1 hit throughout the world. Gramm and Jones were reported as clashing artistically on several occasions during the lifespan of the band; Gramm wanted the band to remain true to its rock origins and favoured music with a drum and guitar base. Jones meanwhile embraced the 1980s style of synthesiser ballads which proved lucrative.

In 1987 during Foreigner's hiatus, Gramm released the album Ready or Not which brought him positive critical reviews and a top five hit single with "Midnight Blue". This was followed by a Foreigner album Inside Information and a second solo album Long Hard Look in 1989, which brought two more solo hits with "Just Between You and Me" reaching the top 10, and "True Blue Love" also reaching the top 40.

Encouraged by his solo success, and still displeased with the direction Foreigner was taking, Gramm left the group to form Shadow King . The new group's 1991 self titled album was released by Virgin Records but was not a success, and the group shortly disbanded. The same year Foreigner released the album Unusual Heat, a relatively unsuccessful effort fronted by Johnny Edwards. Gramm returned to Foreigner in 1992 to record three new songs for the compilation The Very Best of ... and Beyond, and again in 1994 for the album Mr. Moonlight and a well received tour.

In 1997, Gramm was invited by Mick Jones to perform backing vocals on a cover version of "I Want to Know What Love Is" he was producing for the Australian singer Tina Arena. The song went on to become a major hit again throughout Europe. Later in the year, Gramm was diagnosed with a type of brain tumor called a craniopharyngioma . Surgery followed, and although the tumour was benign, it resulted in radiation therapy and a year of rehabilitation. By 1999 Gramm was fit enough to return to working. He continues to work with Jones and Foreigner and in 2004 completed an American tour with Lou Gramm Band.