Girlfriend is a story about two friends, Tanya (Isha Koppikar) and Sapna (Amrita Arora), who have been together since college. The two live together and are very fond of each other. Sapna meets Rahul (Aashish Choudhary) when Tanya is out of town and the two form an intimate relationship. When Tanya returns and learns of this relationship, she is jealous and reacts adversely. As Tanya tries to break their relationship, her true feelings for Sapna come to light.