Baloch appeared in the TV commercials of well known brand names. In 1993, she made her acting debut in the TV serial (PTV Drama) Marvi which was directed by Sultana Siddiqui. Her next series was Dusra Aasmaan. In this serial she performed the role of Abid Ali’s daughter.
In 2000, Mahnoor Baloch started directing and producing her own drama serials. Her first serial as director was Lamhay.
In 2013, she appeared in Geo TV's Eid special play Come On Hum Dum as the wife of co-star Mohib Mirza. She is set to star as the female lead in upcoming Pakistani film Main Hoon Shahid Afridi. For the role, she has filmed an item song Teri Hi Kami alongside Mathira and Humayun Saeed, directed by Saqib Malik and produced and penned by Shani and Kami.
In 2013, Baloch made her Hollywood debut in Torn playing the role of Maryam, a mother whose teenage son is killed in an explosion at a suburban mall.