Kelly, who currently co-hosts US TV show Fashion Police, will play the part of a flight attendant in the tongue-in-cheek B movie.
The film's predecessor Sharknado became a cult classic for being so unrealistic and starred the likes of Tara Reid Ian Zeiring.
Last night, Kelly confirmed to her Twitter followers: "I guess the news is out I'm going to be in #Sharknado2 they asked me & I just could not resist! #SoExcited."
The original flick was made for TV and it is believed the follow up will also only be screened on the box too.
Tara and Ian confirmed last week that they will be returning for The Second One, which will see their characters - Fin and April - head to New York to save residents from sharks that have been thrown onto the street during a tornado.
In the first movie, Los Angeles was destroyed by the same shark-infested disaster.
Sharknado 2: The Second One will also star Taxi's Judd Hirsch - who will play a taxi driver - and Independence Day actress Vivica A. Fox. It will air in July.
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