Haseena is the story of one un-satisfied women who will go to any lengths to get what she wants. Widower JK (Raj Babbar) lives a wealthy lifestyle with his young daughter, Tina (Preeti). He has a very large business enterprise to take care of and finds that he cannot take care of it all by himself he decides to hire a woman named Haseena (Isha Koppikar) and make her his secretary.
He even invites her to live at his home. Soon a young boy, Rahul (Kiran Janjani), son of JK's childhood friend, moves in to stay in JK's bungalow much to the likeness of Haseena. When one night both had physical intimacy with one another and this escalates the likeness in Haseena to a proportion that when Rahul gets married to JK's daughter Tina she cannot even give up on Rahul and must either decides to put an end to Tina's life or to commit suicide.