The fellow James Bond actor penned a heartfelt note after news of his death broke on Saturday.
Connery's wife, Micheline, and his two sons, Jason and Stephane told ET that he died peacefully in his sleep, surrounded by family. As news of his death was announced, Brosnan took to Instagram on Saturday to pay tribute to his fellow Bond.
"Sir Sean Connery, you were my greatest James Bond as a boy, and as a man who became James Bond himself. You cast a long shadow of cinematic splendor that will live on forever," he wrote. "You led the way for us all who followed in your iconic foot steps. Each man in his turn looked to you with reverence and admiration as we forged ahead with our own interpretations of the role."
"You were mighty in every way, as an actor and as a man, and will remain so till the end of time. You were loved by the world, and will be missed. God bless, rest now, be at peace," he concluded.
Connery was the first actor to portray the 007, starring in seven Bond films, beginning with 1962's Dr. No to 1983's Never Say Never Again. Brosnan was the fifth actor to play the secret agent, starring in four films from 1995 to 2002 (GoldenEye, Tomorrow Never Dies, The World Is Not Enough and Die Another Day).
In August, Brosnan wished Connery and happy 90th birthday, sharing a black-and-white photo of the two.
"Happy 90th birthday Sir Sean Connery ... I was eleven years old in 1964, just off the plane from Ireland when I saw Goldfinger at the ABC Cinema on Putney High Street. You were my Bond of inspiration," he penned.
For more on Connery's life and legacy, watch the video above.