Jab Pyaar Kisise Hota Hai is about Sooraj Dhanrajgir (Salman Khan), a rich playboy lightening the financial burden of his industrialist grandfather (Anupam Kher) by spending his riches on alcohol and women. His grandfather calls him for some official work back home, beginning with a hotel project in Ooty. There his true character emerges as he starts running after pretty women. The first one he lays his eyes on is Komal (Twinkle Khanna). He convinces her that she is his childhood friend and sweet-talks her into falling for him. But soon she sees him for the player he is and walks out on him.
Salman and Twinkle
Sooraj is smitten beyond infatuation and, knowing she runs a boutique in a hotel somewhere in Bombay, he goes through the hotels of the city until he locates her. He tries his best to win her back but fails.
Sooraj's grandfather steps in to ease the situation and asks her to marry him. Komal agrees, on the condition that he would have to give up his playboy lifestyle and become responsible: He would have to quit smoking, drinking and women for her to marry him. Sooraj, not quite the man he was, gives up every bad habit he has.
One day Sooraj returns home and he finds a boy, Kabir (Aditya Narayan), claiming to be his son.
Tests prove that Kabir is indeed his son, but Sooraj doesn't even remember the mother (Namrata Shirodkar). Kabir shows him a photograph which helps Sooraj identify the woman he had a fling lasting a few months. He brings the boy back, identifying him as his friend's child. Sooraj starts to like him and gradually, realizing his mistake, he recognises him as his son. But Kabir does not like Komal and is unhappy to learn that Sooraj never loved his mother.
Later Sooraj has to choose between Komal and Kabir. Sooraj is about to marry Komal, but he knows that he cannot hide the truth from Komal. He falls into a dilemma. His friend Mahesh (Johnny Lever) suggests he should tell the truth to Komal about Kabir before their marriage if he really loves her. He tries several times to speak to Komal, but circumstances do not allow him to convey his message.
On the day of their marriage, he lands at her house with his grandfather, Mahesh and Kabir. He accepts his mistakes that he made in life and tells Komal and her family that Kabir is his son. On hearing this Komal's family gets angry and demands Sooraj disown Kabir if he wants to marry Komal. Sooraj refuses to do that and prefers his son over his love.
Komal hails Sooraj's honesty and agrees to accept Kabir as her son and to marry Sooraj.