Stoudemire proposed to Alexis Welch Saturday night on the private terrace of a penthouse overlooking Paris, the New York Post reported.
"I am so honored to be marrying by best friend," Stoudemire said.
His surprise proposal came after a day on a private historical tour of Paris.
"I have been planning my proposal for a while, and [Paris] ... seemed like a perfect place,'' Stoudemire said from Paris. "I am so happy she said yes, and now we can continue to build our life together as husband and wife."
Welsh told the Post the way Stoudemire proposed was special
"Having Amar'e ask me to marry him while overlooking the Paris skyline seemed like some sort of romantic fantasy," she said. "Amar'e put so much care and thought into every detail to make it special for us. We are truly blessed!"
The couple met in 2002 and plan to marry next year. They have three children -- Amar'e Jr., 5, Ar'e, 6, and Assata, 4.
In a Twitter posting, Stoudemire said Sunday night: "When she said yes, it was surreal. I'm still floating."