The former 'Coronation Street' actress will play a lazy agency nurse named Kirsty in an episode of the BBC medical drama airing in July and she is thrilled to have landed the part.
She said: "I'm really pleased to be working in a show I really enjoy."
Oliver Kent, 'Holby City's executive producer, added: "We're delighted to have Helen on the show. She's going to ruffle some feathers.
"So it's definitely an episode to watch."
The 23-year-old beauty recently admitted she struggles to be taken seriously as an actress following her stint on 'I'm A Celebrity... Get Me Out of Here!' in 2012.
She said recently: "I've got a few projects coming up. Reality TV ... I trained as an actress but because I went into the jungle I think sometimes it's hard for people to take you seriously as an actress.
"I'm really open-minded but I am actually a natural born actress, it's my character. But it's because I've done reality TV, and I do enjoy my modelling work. I just like to do things I enjoy, I live for now, I don't think ahead too much."