The virtual awards ceremony will be broadcast on Sunday evening, with much of it pre-recorded at the London Palladium.
The evening will celebrate the winners and nominees as well as honouring those who have made significant contributions to the industry over the past 18 months.
Black is best known for his collaborations with Andrew Lloyd Webber on musicals such as Starlight Express, Sunset Boulevard and Whistle Down The Wind, and for the James Bond theme songs he co-wrote with composer John Barry – Thunderball, Diamonds Are Forever and The Man With The Golden Gun.
He has also worked on productions including Bombay Dreams, Dracula The Musical, Brighton Rock and Feather Boy, as well as Mrs Henderson Presents.
Camilla attended the recording at the theatre on Tuesday, where she quoted the maiden speech made by Laurence Olivier in the House of Lords, saying: “Surely we would all echo Olivier: ‘I believe in the theatre’.
“It is a cornerstone of a fertile cultural life, a forum for debate, and a powerful means of building community.
“After all, a play can be many things – funny, heart-breaking, cathartic, comforting. It can entertain us for an evening, or enrich the soul forever.
“But whatever form a performance takes, it allows us to deepen our understanding of ourselves, others and the world around us.
“Perhaps most importantly, those of us who believe in the theatre also believe in its resilience.
“The last few months have, very sadly, hit theatres and those who work in them extremely hard, just as they have all the live performing arts.
“I was therefore delighted to learn about the creation of the Theatre Artists’ Fund, which has already made an enormous difference to many.
“I should like to thank those of you whose profession is in the theatre for your determination and your flexibility. Please remain resilient – we need you and we have missed you.”
Presenting the special award to Black in the Palladium’s Cinderella Bar, the duchess said: “Don, of course, has lived and breathed the theatre for decades, and his wonderful lyrics have become part of the fabric of our lives.
“I said just now that the theatre is a builder of community. Don, as always, captures this sentiment perfectly in Mrs Henderson Presents with the brilliant line ‘When we’re together, all our woes are gone.’
“Don, you are a great dispeller of woes. Many congratulations on this thoroughly well-deserved award.”
While at the theatre, Camilla met Lord Lloyd-Webber and the co-founders of the Theatre Artists’ Fund, director Sam Mendes and chief executive of the Society of London Theatre Julian Bird, as well as three beneficiaries of the fund.
The fund has raised almost £4 million to date and helped more than 2,600 people.
– The Olivier Awards will be broadcast on October 25 on ITV at 10pm.