The 67 year old - who played Rolfe, the love interest of Liesl Von Trapp - was unimpressed to learn he wouldn't be part of the special Oprah show, which was screened on Thursday (29Oct10).
He tells TMZ.com, "I was the male juvenile lead, a main part of the story... it's beyond me. How can you not include Rolfe?"
But a representative for the show has defended the decision not to include Truhitte in the line-up, insisting, "Our show was a reunion of the von Trapp 'family.' Mr. Truhitte's character was not part of that group."