Rob Mounsey (born December 2, 1952) is an American award-winning composer, music producer, and musician.

He was born in Berea, Ohio, United States, and grew up in Seattle, Washington and several Ohio towns. At the age of 17, he was awarded a 1970 BMI Student Composer Award for his orchestral work Ilium, New York, Is Divided Into Three Parts. He attended Berklee College of Music in Boston from 1971 to 1975. In 1976, he moved to New York to become a noted studio musician, arranger and producer for a wide range of well-known artists, including Rihanna, Aaron Neville, Michael Franks, Carly Simon, Natalie Cole, Diana Krall, Steely Dan, Paul Simon, James Taylor, Chaka Khan, Eric Clapton, Madonna, Diana Ross, Donald Fagen, Brian Wilson, Aztec Camera and countless others. He performed on keyboards in 1981 for Simon and Garfunkel's Concert In The Park.

In 1985, he played keyboards in a New-York-based group called Joe Cool with Will Lee, Jeff Mironov and Christopher Parker. They released one album, Party Animals, on the Pony/Canyon label in Japan, followed by a Japanese tour. Mounsey also released three solo albums as a recording artist: Dig (Sona Gaia, 1990), and two self-released albums on his own Monkeyville label, Back in the Pool and Mango Theory. Mounsey toured as musical director and pianist for Idina Menzel in her Pops Symphony tour, for which he created nearly all of the arrangements.

He has also composed widely for film and television, including the 1988 Mike Nichols film Working Girl (with Carly Simon), the film Bright Lights, Big City (with Donald Fagen), and the HBO hit series Sex and the City. Mounsey also wrote two themes for the television show Guiding Light. He is a six-time Grammy Award nominee, and a winner of two Emmy Awards. He is a Zen Buddhist who resides in Brooklyn, New York.