Motsi will join the panel when the show returns to our screen later this year, having already served as a judge on the German version of the show since 2011.
She said: “I am absolutely overjoyed to be joining the Strictly judging panel. I have so much respect and admiration for the other three judges and hope to add my own bit of sparkle to the show. I can’t wait to get started!”
Motsi replaces departing judge Darcey Bussell, who announced she was stepping down from the show earlier this year.
At the time, Darcey said of her decision to leave: “I have enjoyed every minute of my time and will miss everyone from my fellow judges, the presenters, the dancers, the musicians, the entire backstage team, and especially the viewers of the show, who have been so supportive.
“I am not leaving because of any upset or disagreement at all, I am just stepping away to give more focus to my many other commitments in dance, after seven truly wonderful years that I can’t imagine having gone any better.”
Motsi had served as a professional dancer on Germany’s version of Strictly, Let’s Dance, for four years, until making the shift to the judging panel.
She was recently introduced to UK viewers when she appeared alongside Oti on the celebrity version of Gogglebox.
Interestingly, Oti’s name was among the early rumours to replace Darcey, though she repeatedly said she was keen to remain a professional dancer, rather than serving as a judge.
She told PA last week: “It’s not a job or a title that I ever really wanted. The person who gets it has to have years of experience and know what they are doing.”
Others to have been heavily rumoured for the job include choreographer Mandy Moore, singer Nicole Scherzinger and long-standing Strictly pro Anton Du Beke.
Craig Revel Horwood, Bruno Tonioli and Head Judge Shirley Ballas will all remain with Strictly for the new series, which is expected to launch in September.