Merchant was born into an Ismaili (Aga Khani) family in Mumbai to Siraj Merchant and Rizwana Merchant. She started her career in 1997 with the TV show Shaktimaan, in which she played Julia, an assistant. She then played Nonie in the popular show Hip Hip Hurray from 1998 to 2000. Kishwar then appeared in many successful popular shows like Babul Ki Duwayen Leti Jaa, Des Mein Niklla Hoga Chand, Kutumb, Kasautii Zindagii Kay, Kayaamat, Hatim and Khichdi.