| Movie | 1982 | Star Trek II: The Wrath of Khan | Cmdr. Montgomery 'Scotty' Scott | |
| Movie | 1979 | Star Trek: The Motion Picture | Cmdr. Montgomery 'Scotty' Scott | |
| Movie | 1984 | Star Trek III: The Search for Spock | Captain Montgomery 'Scotty' Scott | |
| Movie | 1986 | Star Trek IV: The Voyage Home | Captain Montgomery 'Scotty' Scott | |
| Movie | 1989 | Star Trek V: The Final Frontier | Captain Montgomery 'Scotty' Scott | |
| Movie | 1991 | Star Trek VI: The Undiscovered Country | Captain Montgomery 'Scotty' Scott | |
| Movie | 1994 | Star Trek: Generations | Captain Montgomery "Scotty" Scott | |
| Movie | 1966 | Fantastic Voyage | Dr. Sawyer (Hypothermia technician) (uncredited) | |
| Movie | 1991 | Warp 3 - The Official Convideo | Self | |
| Movie | 1997 | Trekkies | Self | |
| Movie | 1966 | Scalplock | Scrimp | |
| Movie | 1971 | Man in the Wilderness | Benoit | |
| Movie | 1968 | Jigsaw | Building Superintendent (uncredited) | |
| Movie | 1971 | Pretty Maids All in a Row | Follo | |
| Movie | 1998 | Bug Buster | Sheriff Carlson | |
| Movie | 1998 | Cold Fusion: Fire from Water | Himself | |
| Movie | 1999 | The Duke | Clive Chives | |
| Movie | 1963 | The Wheeler Dealers | Defense Attorney (uncredited) | |
| Movie | 1994 | Storybook | Uncle Monty | |
| Movie | 1999 | Through Dead Eyes | Barney Fredericks | |
| Movie | 1964 | 36 Hours | Bishop (uncredited) | |
| Movie | 1993 | Amore! | Dr. Landon | |
| Movie | 1996 | The Making of Star Trek Deep Space Nine Trials And Tribble-ations | Self | |
| Movie | 1996 | William Shatner's Star Trek Memories | Self | |
| Movie | 1975 | The Star Trek Dream | Self | |
| Movie | 1994 | William Shatner: Captain's Log | Self | |
| Movie | 1991 | Star Trek: 25th Anniversary Special | Self | |
| Movie | 1994 | Star Trek: A Captain's Log | Himself | |
| Movie | 1991 | Knight Rider 2000 | James 'Scotty' Doohan | |
| Movie | 1993 | National Lampoon's Loaded Weapon 1 | Scotty | |
| Movie | 1965 | Bus Riley's Back in Town | Les | |
| Movie | 1992 | Double Trouble | Chief O'Brien | |
| Movie | 1965 | The Satan Bug | Second Agent "X-Ray", scratches hand | |
| Movie | 1966 | One of Our Spies Is Missing | Phillip Bainbridge | |
| Movie | 1997 | UFOs Above and Beyond | Host | |
| Movie | 1965 | Willy McBean & His Magic Machine | (voice) | |
| Movie | 2016 | Star Trek: Inside the Roddenberry Vault | (archive footage) | |
| Movie | 1966 | Star Trek: The Menagerie | Scott | |
| Movie | 1956 | Flight Into Danger | George Spencer | |
| Movie | 1996 | Star Trek: 30 Years and Beyond | Self | |
| Movie | 2022 | Way of Tomorrow: The Evolution of Science Fiction Movies | Self - (archive footage) | |
| Movie | 2011 | Underground Entertainment: The Movie | James (archive footage) | |
| TV Show | 1980 | Magnum, P.I. | Archie MacPherson | 1 |
| TV Show | 1992 | The Ben Stiller Show | | 1 |
| TV Show | 1994 | Duckman | Kardassian (voice) | 1 |
| TV Show | 1962 | The Gallant Men | | 1 |
| TV Show | 1966 | Star Trek | Scott | 79 |
| TV Show | 1987 | Star Trek: The Next Generation | Scotty | 1 |
| TV Show | 1965 | The F.B.I. | Claude Bell | 1 |
| TV Show | 1996 | The Daily Show | Self | 1 |
| TV Show | 1973 | Star Trek | Montgomery Scott (voice) | 22 |
| TV Show | 1969 | Marcus Welby, M.D. | Detective Sgt. Brenner | 1 |
| TV Show | 1982 | Hotel | | 1 |
| TV Show | 1985 | MacGyver | Speedy | 1 |
| TV Show | 1963 | The Fugitive | Doctor | 1 |
| TV Show | 1959 | The Twilight Zone | Father | 1 |
| TV Show | 1965 | Laredo | | 1 |
| TV Show | 1964 | Daniel Boone | Bruce MacFarland | 1 |
| TV Show | 1963 | The Fugitive | Deputy | 1 |
| TV Show | 1978 | Jason of Star Command | Commander Canarvin | 16 |
| TV Show | 1962 | The Virginian | George Mitchell | 1 |
| TV Show | 1996 | Homeboys in Outer Space | Pippen | 1 |
| TV Show | 1957 | Hawkeye and the Last of the Mohicans | Harris | 1 |
| TV Show | 1961 | Ben Casey | | 1 |
| TV Show | 1961 | The New Breed | Dr. Lennon | 1 |
| TV Show | 1951 | Tales of Tomorrow | | 1 |
| TV Show | 1962 | General Electric True | | 2 |
| TV Show | 1964 | Bewitched | Walter Brocken | 1 |
| TV Show | 1964 | The Rogues | Cutler | 1 |
| TV Show | 1995 | Charlie Grace | Self | 1 |
| TV Show | 1964 | The Man from U.N.C.L.E. | Phillip Bainbridge | 1 |
| TV Show | 1962 | The Virginian | James Francis O'Bannion | 1 |
| TV Show | 2021 | Star Trek: Prodigy | Scotty (voice) | 1 |
| TV Show | 1953 | Space Command | Phil Mitchell, XSW1 Engineer | 13 |
| TV Show | 1963 | The Outer Limits | Police Lt. Branch | 1 |
| TV Show | 1985 | Danger Bay | Pete | 1 |
| TV Show | 1964 | Daniel Boone | Fletcher | 1 |
| TV Show | 1955 | Folio | | 4 |
| TV Show | 1959 | Bonanza | Bill Collins | 1 |
| TV Show | 1965 | The F.B.I. | Frank Delbey | 1 |
| TV Show | 1959 | Bonanza | Colonel's Man | 1 |
| TV Show | 1964 | Voyage to the Bottom of the Sea | Lawrence Tobin (uncredited) | 1 |
| TV Show | 1949 | Suspense | Peters | 1 |
| TV Show | 1964 | The Man from U.N.C.L.E. | Mr. MacInernay | 1 |
| TV Show | 1955 | Gunsmoke | Davit | 1 |
| TV Show | 1961 | Hazel | Gordon MacHeath | 1 |
| TV Show | 1954 | On Camera | | 4 |
| TV Show | 1969 | Marcus Welby, M.D. | Fred Baxter | 1 |
| TV Show | 1957 | Hawkeye and the Last of the Mohicans | Tonkawa | 1 |
| TV Show | 1964 | Voyage to the Bottom of the Sea | Presidential Assistant | 1 |
| TV Show | 1955 | First Performance | | 2 |
| TV Show | 1955 | First Performance | Joynt | 1 |
| TV Show | 1969 | Then Came Bronson | Dr. John Wilson | 1 |
| TV Show | 1993 | Star Trek: Deep Space Nine | Mr. Scott | 1 |
| TV Show | 1966 | Jericho | Pastor Lutjens | 1 |
| TV Show | 1965 | Convoy | Lt. Wells | 1 |
| TV Show | 1966 | Blue Light | Conners | 1 |