Nielsen died of complications of pneumonia in a hospital near his home in Fort Lauderdale, Fla., his family said Sunday. He was 84.
The actor was best known for his roles in the "Naked Gun" and "Airplane!" movies, as well as for his appearances on TV's "Police Squad!" "Goodyear Playhouse" and "Hawaii Five-O."
His other film credits included "Forbidden Planet" and "The Poseidon Adventure."
CNN said the actor was declared an Officer of the Order of Canada in 2003.
UsMagazine.com said numerous stars offered their condolences via Twitter upon hearing the news of Nielsen's death.
TV and radio personality Ryan Seacrest tweeted: "Sad to hear about Leslie Nielsen passing. To this day 'Airplane' is still one of my favorite comedies ever."
"RIP. Leslie Nielsen. Shirley, he will be missed," Russell Brand said in his own message.
Musician Slash said via Twitter: "RIP Leslie Nielson, one of my all time favorite comedians. U my friend, will be missed big time. Wow, what a loss. Iii|: ( '& don't call me Shirley.'"