| Year of release | Collaborated with | Song | Album/Record | May's contribution
Guitar unless stated |
|---|
| 1975 | Eddie Howell | "Man from Manhattan" | Man from Manhattan | backing vocals and guitar (piano and backing vocals by Freddie Mercury) |
| 1976 | Ian Hunter | "You Nearly Did Me In" | All-American Alien Boy | backing vocals by May, Mercury and Roger Taylor |
| 1978 | Lonnie Donegan | "Digging My Potatoes" | Puttin' on the Style | |
| 1980 | Quartz | "Circles" (recorded in 1977) | B-side of the single "Stoking the Fires of Hell" (1980); also bonus track on the 2004 reissue of the album Stand Up and Fight | |
| 1983 | Jeffrey Osborne | "Stay with Me Tonight", "Two Wrongs Don't Make a Right" | Stay with Me Tonight | |
| 1984 | Billy Squier | "(Another) 1984" | Signs of Life | |
| 1985 | Chris Thompson | "A Shift in the Wind, Parts 1 and 2" | Radio Voices | |
| 1986 | Ramoncín | "Como un susurro" | La vida en el filo | |
| 1988 | The Cross | "Love Lies Bleeding (She Was a Wicked, Wily Waitress)" | Shove It | |
| 1989 | Holly Johnson | "Love Train" | Blast | |
| Living in a Box | "Blow the House Down" | Gatecrashing | |
| Black Sabbath | "When Death Calls" | Headless Cross | guitar solo |
| Fuzzbox | "Self!" | Big Bang! | |
| Artists United for Nature | "Yes We Can" | Yes We Can(single; also released on the compilation Earthrise – The Rainforest Album) | |
| Rock Aid Armenia | "Smoke on the Water" | "Smoke on the Water" | guitar (drums by Roger Taylor) |
| 1990 | Rock Against Repatriation | "Sailing" | "Sailing" | |
| 1991 | D-Rok | "Red Planet Blues", "Get Out of My Way" | Oblivion | |
| 1992 | Extreme | "Love of My Life" | Song for Love(for the Terence Higgins Trust) | |
| Judie Tzuke | "I Can Read Books" | Wonderland | |
| Phenomena | "A Whole Lot of Love" (recorded in 1988) | Phenomena III: Inner Vision | |
| Tony Martin | "If There Is a Heaven" | Back Where I Belong | |
| Cozy Powell | "Somewhere in Time" (instrumental version of "Nothin' But Blue"], "Ride to Win" | The Drums Are Back | guitar (bass by John Deacon on "Somewhere in Time") |
| Steve Hackett | "Don’t Fall Away from Me" (recorded in 1986) | The Unauthorised Biography | |
| 1993 | Paul Rodgers | "I'm Ready" | Muddy Water Blues: A Tribute to Muddy Waters | |
| Steve Hackett | "Cassandra" (recorded in 1986) | Guitar Noir(bonus track) | |
| The Left Handed Marriage | "Appointment", "She Was Once My Friend", "I Need Time" (recorded in 1967) | Crazy Chain | guitar, backing vocals; I Need Time written by Bill Richards and May |
| 1994 | Os Paralamas do Sucesso | "El Vampiro Bajo El Sol" | Severino | |
| 1995 | Jennifer Rush | "Who Wants to Live Forever" | Out of My Hands | vocals and guitar |
| Gordon Giltrap | "Heartsong" (recorded in 1993) | Music for the Small Screen | |
| Carmine Appice | "Nobody Knew (Black White House)" | Carmine Appice's Guitar Zeus | |
| S.O.L. (Stefan Zauner) | "Make My Dream Come True" | S.O.L. – Some Other Language | |
| 1996 | Status Quo | "Raining in My Heart" | Don't Stop | |
| Rock Therapy | "Reaching Out" | Reaching Out
(single; for the Nordoff-Robbins Music Therapy Centre) | |
| 2000 | Steve Hackett | "Slot Machine" (recorded in 1986) | Feedback '86 | |
| Tony Iommi | "Goodbye Lament" (featuring Dave Grohl), "Flame On" (featuring Ian Astbury) | Iommi | |
| Freddie Mercury | "She Blows Hot and Cold (Alternative Version)" (recorded in 1984) | The Solo Collection (box set) | |
| Foo Fighters | "Have a Cigar" | Mission: Impossible 2 (soundtrack) | |
| 2002 | Michael Kamen | "Light the Fire Within" | unreleased; official theme of the 2002 Winter Olympics | |
| Claire Sweeney | "Too Much Love Will Kill You" | Claire | |
| Foo Fighters | "Tired of You" | One by One | |
| 2003 | The Yardbirds | "Mr. You're a Better Man Than I" | Birdland | |
| Tim Staffell | "Earth", "Doin' Alright" | Amigo | guitar & vocals |
| 2004 | Zucchero | "Il mare impetuoso al tramonto salì sulla luna e dietro una tendina di stelle..." | Zu & Co. | |
| 2006 | Meat Loaf | "Bad for Good" | Bat Out of Hell III: The Monster Is Loose | |
| 2007 | Lynn Carey Saylor | "We Belong" [26] | You Like It Clean | guitar & background vocals |
| Guns N' Roses | "Catcher in the Rye (Demo)" | Chinese Democracy (sessions) | Uncredited guitar solo |
| 2008 | Minako Honda | "Amazing Grace (Traditional) Produced by Brian May" | Eternal Melody | Arrangement, backing vocals, keyboards, toy koto, production |
| Kerry Ellis | "Defying Gravity", "I'm Not that Girl", "No-One but You (Only the Good Die Young)" | Wicked in Rock | Arrangement, bass, guitars, keys, production, programming |
| 2010 | "Dangerland", "Anthem", "I Can't Be Your Friend (This Can't Be Over)", "Defying Gravity", "I'm Not that Girl", "You Have to Be There", "Love It When You Call", "Save Me", "Diamonds Are Forever", "No-One but You (Only the Good Die Young)", "I Loved a Butterfly" | Anthems | Arrangement, backing vocals, bass, guitars, piano, keyboards, production |
| Taylor Hawkins and the Coattail Riders | "Way Down", "Don't Have to Speak" | Red Light Fever | guitar |
| Meat Loaf | "Love Is Not Real", "The Song of Madness" | Hang Cool Teddy Bear | |
| 2011 | Tangerine Dream | | Starmus – Sonic Universe | |
| Lady Gaga | "You and I" | Born This Way | guitar |
| 2015 | Motörhead | "The Devil" | Bad Magic | guitar solo |
| 2020 | Woman | "I'm a Woman" | "I'm a Woman" | guitar & production |
| Live Recordings (Selection) |
|---|
| 1988 | Prince's Trust Gala Concert | | Prince's Trust Rock Gala(VHS; recorded live at the Royal Albert Hall on 6 June 1988) | guitar (bass by Deacon) |
| 1992 | Pavarotti and Friends | "Too Much Love Will Kill You", "La donna è mobile" | Pavarotti & Friends (VHS; recorded live in Modena on 27 September 1992) | |
| 2005 | The Strat Pack | "Peggy Sue", "Maybe Baby", "I Fought the Law", "Oh Boy!", "That'll Be the Day" (with The Crickets and Albert Lee); "All Right Now" (with Paul Rodgers) | The Strat Pack: Live in Concert (DVD; recorded live at the concert from the 50th Anniversary of the Fender Stratocaster guitar on 24 September 2004) | |
