Her manager, Marion Rosenberg, confirmed her passing Saturday to some outlets -- with him telling Variety, "A beautiful human being and one of the great talents of our time." He further shared with THR that she'd been ill now for quite some time ... although an exact cause of death wasn't revealed.

Laurie was one of the last few stars from Hollywood's golden era -- having gotten her start in showbiz back in the '50s ... starring in movies alongside some very famous names, including Donald O'Connor, Tony Curtis, Rock Hudson, Tyrone Power and even Ronald Reagan.

Speaking of the late President -- with whom she acted in her breakout film, "Louisa" -- PL once claimed she'd lost her virginity to him ... and they even dated for a while pre-Nancy. Throughout that decade, she was on a tear ... but took a break until 1961, when she starred opposite Paul Newman in "The Hustler" -- for which she won a Best Supporting Actress nom.

After another long hiatus, Laurie came back to the big screen for her memorable role as Margaret White ... Sissy Spacek's mother in the horror classic, 'Carrie,' for which she won another Best Supporting Actress nomination. Ditto for 1986's 'Children of a Lesser God.'

One of her other very famous parts was in the show "Twin Peaks" ... where she played Catherine Martell AND Mr. Tojamura. The latter performance was iconic. She actually won a Golden Globe for her work on 'TP' ... not to mention an Emmy for a TV movie as well.

Laurie's career was long and prosperous ... having starred in other huge films such as "The Bunker," "Return to Oz" and more. Her TV appearance might've been even more prolific -- she acted in series like 'ER,' 'Skag,' 'The Twilight Zone,' 'Traps,' "Touched By an Angel," "Frasier," "Will & Grace," "Law & Order," "MacGyver" ... and so many others.

She was 91.