The actress, who played the role of Lisa Hunter on the Chester-based soap will join the Hotten based serial drama later this year as Carly comes to the village feeling that her dad Bob ought to make up for lost time, having missed out on her life whilst she was growing up.
However, as he begins to get to know his daughter, life will soon become difficult for the cafe owner. Carly has also been unlucky in love and is hoping that a move will lead to better luck.
The actress said: ''I am absolutely thrilled to be joining the cast of Emmerdale and I cannot wait to see what's in store for Carly. I hope you all enjoy watching her story unfold."
Meanwhile, the show's series producer, Kate Oates teased: ''I'm delighted to welcome Gemma to the cast. Her character Carly is sure to liven things up for Bob and Brenda and anyone who crosses her path."
Carly has briefly appeared in the soap previously in 2006, played then by former Waterloo Road and Shameless star Rebecca Ryan.
Since leaving Hollyoaks in 2005, 30-year-old Atkinson has appeared in Casualty as paramedic Tamzin and had a stint in the jungle in I'm A Celebrity Get Me Out Of Here.