Amitabh, 73, will be seen making a cameo with his actress-politician wife Jaya for the film, which also stars actress Kareena Kapoor Khan.
The 'Ishaqzaade' star also said that it was a "surreal moment" for him to work with Big B.
"A surreal moment when you work with coolest actor/star in our industry. Felt like a child on set with him Amitabh Bachchan," Arjun tweeted.
Directed by R. Balki, 'Ki & Ka' revolves around gender equality. Arjun plays the role of a house husband, while Kareena plays a career-oriented woman.
This is not the first time that Amitabh has been a part of Balki's film.
The cine-icon has worked with the talented filmmaker in films like 'Paa', 'Shamitabh' and 'Cheeni Kum'.
