Christie, who holds the current UK number one single with Is This The Way To Amarillo?, featuring comedian Peter Kay, will appear as himself on the soap when he duets with Diane (Elizabeth Estensen).
He will meet some of the characters when they are on an excursion to Newcastle in an episode which will be broadcast in August.
Waveguide quotes Christie as saying: "My mum is more impressed that I will be on Emmerdale than she is with my number one single."
He added that he is a long-time fan of the show and is looking forward to making an appearance.
A spokeswoman for the soap said: "We are delighted that Tony is available to appear in this unique episode which is going to be a lot of fun.
"Tony will be performing one of his songs and will cause a stir by inviting Diane to join him on stage."
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