The actress is producing the stage version of the 1992 film and it was initially presumed that she would not feature in the production.
However, it was confirmed in July that Goldberg would join the cast in August. For three weeks, the star will take over from Sheila Hancock in the role of Mother Superior.
According to Yahoo, the 54-year-old said: "It's a big deal. It's The Palladium and it's London, and it's my first stage production here that I'm in."
The musical will move to New York's Broadway at the end of this year.