Donald Douglas MacKay (July 8, 1931 - September 2, 2024) was a Canadian actor with more than 40 years on-screen experience.

He made guest appearances on such series as Airwolf, MacGyver, Highlander, Sliders, The X-Files, Stargate SG-1, Smallville, The Dead Zone, Supernatural and Bates Motel.

He appeared in three episodes of the revival series from 1995 to 1999:

• "I, Robot (1995)" - Dr. Charles Link
• "Feasibility Study" - Pat Dooley
• "The Inheritors" - Ollie Gibb

Coincidentally, all three episodes were remakes of episodes of the original series: "I, Robot", "A Feasibility Study" and its only two-part story "The Inheritors, Part I" and "The Inheritors, Part II". The only remake episode in which he did not appear is "Nightmare (1998)".