The 42-year-old Luther actor has been dating beauty queen Sabrina, 29, since they met while Idris was filming The Mountain Between Us with Kate Winslet in Canada last year.
Rio Cinema in Dalston, London, confirmed the happy news alongside an Instagram video of Elba's proposal.
Meeting Sabrina clearly gave Idris a change of heart, however. Still 5 days to Valentines Day but @idriselba went down on one knee and proposed to his girlfriend live on stage this morning before a preview of his film #Yardie'.
Idris Elba turned a movie screening into an unforgettable night.
Gerry Adams to hand over Sinn Féin leadership to Mary Lou McDonald
She was appointed Sinn Fein's deputy leader in 2009 and has represented central Dublin in the Irish parliament since 2011. Her father, Brendan "Basil" Doris, was a former IRA prisoner who became a Sinn Fein councillor in Dungannon.
Idris Elba and His Former Miss Vancouver Girlfriend Make Their Red Carpet Debut at TIFF - See the Pics!
"Am I ever gonna get remarried?" Marriage is an institution of sorts. "It's not my life's calling".
Entertainment Daily contacted Idris's publicists for a comment on his reported engagement but are yet to receive a response.
Idris has a 15-year-old daughter, named Isan, from his marriage to Norgaard, and he shares a three-year-old son, called Winston, with ex-girlfriend Naiyana Garth, who he split from in 2016.