Lifeson was born as Alexandar Zivojinovich (Aleksandar Živojinović/Александар Живојиновић in Serbian) in Fernie, British Columbia, to Serbian immigrants, Nenad and Melanija Živojinović, and raised in Toronto, Ontario. His stage name of "Lifeson" is a semi-literal translation of the surname Živojinović, which means "son of life" in Serbian. His first exposure to formal music training came in the form of the viola, which he renounced for the guitar at the age of 12. His first guitar was a Christmas gift from his father, a six-string Kent classical acoustic which was later replaced by an electric Japanese model. During his adolescent years, he was influenced primarily by Jimi Hendrix, Pete Townshend, Jeff Beck, Eric Clapton, Jimmy Page, Steve Hackett, and Allan Holdsworth; he explained in 2011 that "Clapton's solos seemed a little easier and more approachable. I remember sitting at my record player and moving the needle back and forth to get the solo in 'Spoonful.' But there was nothing I could do with Hendrix." In 1963, Lifeson met future Rush drummer John Rutsey in school. Both interested in music, they decided to form a band. Lifeson was primarily a self-taught guitarist with the only formal instruction coming from a high school friend in 1971 who taught classical guitar lessons. This training lasted for roughly a year and a half.
In 2011, Lifeson said that for the past few years he "...used Gibson almost exclusively. There's nothing like having a low-slung Les Paul over my shoulder."
In early 2011, Gibson introduced the "Alex Lifeson Axcess", a guitar specially designed for him. These are custom made Les Pauls with Floyd Rose tremolo systems and piezoacoustic pick-ups. He used these two custom Les Pauls on the Time Machine Tour. These guitars are also available through Gibson, in a viceroy Brown or Crimson colour. Lifeson used these two guitars heavily on the tour.