Kenneth Ross MacKenzie (June 15, 1912 – July 3, 2002) was an American nuclear physicist.

MacKenzie devised MacKenzie buckets which are plasma sources created by lining vacuum chamber walls with permanent magnets of alternating polarity to suppress plasma electron losses, that are widely used to this day.

[2] As a graduate student, Kenneth Ross Mackenzie was involved in the Manhattan Project to help solve how to separate the rare uranium-235 isotope from the identical dominant uranium-238 isotope at Oak Ridge, Tennessee.

[3] While working on the Manhattan project, MacKenzie and colleagues borrowed 14,700 tons of silver from the US Treasury and melted it into strands to replace old copper in their magnetic coils.

[4] As an actor, he played minor roles with Yvonne De Carlo in Ride the Pink Horse (1947), River Lady (1948) and Black Bart (1948).