The Grammy Award for Best Musical Theater Album has been awarded since 1959. The award is generally given to the album's producers, principal vocalist(s), and the composer and lyricist if they have written a new score which comprises 51% or more playing time of the album, though the number of recipients has varied over the category's tenure.

The inaugural award was presented at the 1st Grammy Awards to composer Meredith Willson for his work on his 1957 musical The Music Man. Ethel Merman and Gwen Verdon became the first female recipients the in 1960 when they tied for Gypsy and Redhead. Stephen Sondheim and Thomas Z. Shepard hold the record for most wins in the category, with six each, while Sondheim holds the record for most nominations, with eleven. Tommy Krasker holds the record for most nominations without a win, with eight. To date, two-time recipient Phillipa Soo is the only woman to win more than one award. Among shows, cast recordings from Gypsy, West Side Story, Into the Woods, and Sweeney Todd: The Demon Barber of Fleet Street have been nominated four times each respectively, with Gypsy, West Side Story, Into the Woods, and Les Misérables are the only shows to win twice. Anything Goes, Hello, Dolly!, The King and I, and My Fair Lady hold the record for most nominations without a win, with three. The current recipient of the award is Some Like It Hot, which won at the 66th Annual Grammy Awards in 2024.

Over the years, the qualifications for the individual nominees has fluctuated with principal artists, composers, and producers at one point being the sole eligible nominee, to the current (as of the 66th Grammy Awards) standard which is as follows: "For albums containing greater than 51% playing time of new recordings. Award to the principal vocalist(s), and the album producer(s) of 50% or more playing time of the album. The lyricist(s) and composer(s) of 50 % or more of a score of a new recording are eligible for an Award if any previous recording of said score has not been nominated in this category."

Vocalists were first awarded in this category at the 54th Annual Grammy Awards in 2012. When an album does not feature any individual soloists and predominantly features an ensemble cast, no individual award is given to the members of the ensemble, with each member instead receiving a winners certificate. As of the 63rd Annual Grammy Awards, only a maximum of four principle vocalists can be awarded (previously unlimited), in addition to the producer/s and lyricists/composers.^[1]

Years reflect the year in which the Grammy Awards were handed out, for music released in the previous year.

This award has had several minor name changes:

• In 1959 the award was known as Best Original Cast Album (Broadway or TV)
• In 1960 it was awarded as Best Broadway Show Album
• In 1961 it was awarded as Best Show Album (Original Cast)
• From 1962 to 1963 it was awarded as Best Original Cast Show Album
• From 1964 to 1973 it was awarded as Best Score From an Original Cast Show Album
• From 1974 to 1975 it was awarded as Best Score From the Original Cast Show Album
• From 1976 to 1986 it was awarded as Best Cast Show Album
• From 1987 to 1991 it was awarded as Best Musical Cast Show Album
• From 1992 to 2011 it was awarded as Best Musical Show Album
• From 2012 it has been known as Best Musical Theater Album.^[2]