Aftab Shivdasani was selected as the Farex baby (baby food brand) at age 14 months and from that point on he appeared in many TV commercials. He made his Bollywood debut as a child actor in Mr. India (1987), then appearing in films such as Awwal Number, Shahenshah, ChaalBaaz and Insaniyat. He also played the child role for Inspector Vijaykumar Srivastav in the 1988 film 'Shahenshah', who would later be played by Amitabh Bachchan for the remainder of the film.

In 2000, Shivdasani won the Zee Cine Award for Best Male Debut and the Star Screen Award for Most Promising Newcomer – Male for his performance in Mast. He earned critical acclaim for his performance. Mohammad Ali Ikram of Planet Bollywood praised his performance and wrote: "Newcomer Aftab Shivdasani comes across as a bit young and aimless when the movie opens, but as you watch the proceedings, you'll learn that this bit of casting makes perfect sense considering Kittu's immaturity and innocence."

In 2001, Shivdasani made his comeback to acting with his second film, Vikram Bhatt’s Kasoor opposite the debutant Lisa Ray. Shivdasani played a negative role and shot to instant fame with his portrayal of Shekhar Saxena, a well-known journalist, who murders his wife. His performance in the film earned him a nomination for the Filmfare Best Villain Award and a Zee Cine Award for Best Actor in a Negative Role. Taran Adarsh of Bollywood Hungama noticed the improvement in his acting and praised his performance. "Aftab, as the suave publishing magnate, catches you unaware with a performance that is first-rate. His characterisation is dissimilar from the one he played in his debut-making venture Mast. His work should catapult him to the league of genteel artists." His next release of that year saw him paired with Ram Gopal Varma again after Mast in Love Ke Liye Kuch Bhi Karega, in which Shivdasani starred in a supporting role opposite Saif Ali Khan, Fardeen Khan, Twinkle Khanna and Sonali Bendre. 
In 2002, Shivdasani's first two films Koi Mere Dil Se Poochhe opposite debutant Esha Deol was a failure but Kya Yehi Pyaar Hai opposite Ameesha Patel was successful at the box office. His third release of that year was Rajkumar Kohli's multi-starrer supernatural horror Jaani Dushman: Ek Anokhi Kahani that was anithet flop. His fourth film of 2002 was the multi-starrer action comedy Awara Paagal Deewana, that proved to be a successful movie and became the seventh highest grosser movie of that year. It was his only hit movie of 2002. His final release of that year was Pyaasa.

Shivdasani had some success in 2003 with the multi-starrer Darna Mana Hai, which was a critical success. His role of Purab, a young college student who has the ability to stop and move people, was critically praised. His next release was Priyadarshan's comedy film Hungama opposite Akshaye Khanna and the debutant Rimi Sen, which was his second success of that year. His third and final release of that year was Footpath opposite Bipasha Basu, Rahul Dev and debutant Emraan Hashmi, which failed to do well at the box office.

In 2005, Shivdasani's films included Mr Ya Miss opposite Antara Mali and Koi Aap Sa opposite Natassha.