Poornima started her career as a model and then went on to host the music countdown show Pepsi Top Ten on Asianet. She acted in many successful television serials such as Oomakkuyil, Sthree oru Santhwanam, Venalmazha, Nizhalukal and Kolangal in Tamil. She has also acted in a few movies, including Meghamalhar, Valliettan and Randam Bhavam. She received the best supporting actress award for her role in Meghamalhar.
In late 2000's she returned toto hosting with the show Mega Swarnamazha in Surya TV. Later she hosted the successful television shows like Kadha Ithu Vare, Idavelayil, Kuttikalodano Kali and Made for each other season 2 on the channel Mazhavil Manorama. She has appeared in many advertisements too.
She is a talented dancer also. She has now become a fashion designer. She runs a boutique by the name "Pranaah" in Kochi. She writes a regular column named "In Style" for "Chithrabhumi", a supplement of Mathrubhumi.