Jab Pyaar Kisise Hota Hai (transl. When one falls in love) is an Indian Hindi-language romance film released in 1998. Directed by Deepak Sareen and written by Honey Irani, the film stars Salman Khan as womaniser Sooraj and Twinkle Khanna as his first real love. Aditya Narayan plays Khan's previously unknown son.
 Sooraj Dhanrajgir, a rich playboy lightening the financial burden of his industrialist grandfather by spending his riches on alcohol and women, and Mahesh, who is having 350 ailments and takes medicine for each of his sicknesses and is sent to take care of Sooraj. His grandfather calls him for some official work back home, beginning with a hotel project in Ooty. When Mahesh was figuring out if he had taken all the medicines, his grandfather was asking him what Sooraj does, Mahesh reveals everything as he was offered a drink. One day, during his grandfather's birthday, he was not at home but at some residence along with another woman. Mahesh is held responsible for all his misdeeds, and Sooraj finds out that he doesn't remember his grandfather's birthday Sooraj gets to blame as he is smitten with pretty women and nothing else. Sooraj tries to give a white rose to his grandfather and instead of seeking forgiveness, he blames his grandfather that he didn't give him the chance to wish him a happy birthday. During the night time, Sooraj and Mahesh drink a lot in happiness at a bar and Mahesh explains that Sooraj's grandfather concerns a lot and Mahesh is even considered kin as he was raised by Sooraj's grandfather. Meanwhile, an argument ensues between a bartender and the guards when the bartender insults his grandfather. He and Mahesh beat all of them and warns the bartender not to insult the seniors of the family. Sooraj and Mahesh arrive home late in the morning, lying that both of them are going jogging and wearing suits as there's cold outside. His lies and excuses don't even work when his grandfather wears the same attire that Sooraj and Mahesh were wearing and he finds out that they were left behind by their grandfather as they were drunk. There his true character emerges as he starts running after pretty women. The first one he lays his eyes on is Komal. 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.
 Sooraj is smitten beyond infatuation and, knowing she runs a boutique in a hotel somewhere in Mumbai, he goes through the hotels of the city until he locates her. He tries his best to win her back but fails when the truth is revealed that he's not his childhood friend but a famous playboy shown in the magazines.
 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. Due to his commitment, he's admitted to a hospital for not drinking alcohol. Komal misunderstands him and tries to leave him but after knowing the truth from his grandfather that she changed him totally, she reciprocates with him.
 One day Sooraj returns home and he finds a dog named Sandy, and a boy, Kabir, claiming to be his son. Sooraj is confused if the young child is either pranking him or not, he goes to a hospital for a medical test, which even proves that Kabir is his biological son, but he doesn't remember his mother. He asks his mother's name, and who raised him, he even asks how did he get the location where he lives, and Kabir answers all of his questions. He even tries to send him to an orphanage but fails mysteriously and the child again appears at his residence, he goes to a restaurant with him. Mahesh eventually reaches there, asks the child's name, and is shocked to find that he's Sooraj's son. Mahesh even asks if he hadn't done anything bad. Sooraj explains everything to Mahesh. The mayhem continues even when he's at home or somewhere else.
 Sooraj goes to London for Kabir's education without informing his grandfather, and Mahesh gives an excuse that one of his friends is in a serious condition and he has gone to visit him. Kabir passes the admission test in a boarding school for his intelligence, and the principal of the school tells Sooraj and Kabir to come next Monday. One day, after carrying everything and packing for school, Kabir shows him a photograph that helps Sooraj identify the woman he had a fling with for a few months. Sooraj remembers everything and repents it. He consoles Kabir on a day and spends a lot of time together before Kabir got admitted to the school. He eventually brings the boy back, identifying him as his friend's child to his grandfather. Sooraj starts to like him and gradually, realizing his mistake, he recognizes him as his son. Kabir does not like Komal and is unhappy to learn that Sooraj never loved or married his mother. When Sooraj was playing cricket, Komal calls Sooraj but Kabir holds the line and says that he's busy playing cricket. Komal then goes to his residence and wants 2 minutes to speak, but Sooraj doesn't get it. Komal understands who the child is and explains everything that happened after she called him on the phone, Sooraj then calls Kabir and tells him to seek forgiveness from Komal. Kabir, residing his hate towards Komal, seeks forgiveness from her and Komal forgives him. When Sooraj and Komal were out on a date, Kabir calls Sooraj on the phone as he felt hungry. Sooraj replies to him to have his dinner, brush his teeth and take a nap. Komal says that he did a good thing that he didn't cancel the date. While Kabir and his great-grandfather was playing chess, Kabir defeats him and keeps his word to keep a dog inside his home. One day, when Sooraj and Komal's program before the marriage date was getting fixed, Kabir goes to his room and Sooraj goes after him. Kabir stops Sooraj and says that she is not like his mother and he even adds that Sooraj never married Kabir's mother. Sooraj tries to console him that Komal will take nice care of Kabir but he disagrees with it. Komal interrupts the conversation and Kabir is infuriated and scolds her a lot, adding that he is discussing an important matter with Sooraj. This enrages Sooraj and he slaps Kabir, telling him an insolent boy. Sooraj finds out that Komal is also disturbed and tells him that Kabir is a nuisance in their relationship. Meanwhile, at the same time, Kabir calls her on the phone, seeks forgiveness from Komal, and tells her that he'll never do this again to her. They soon reconcile after Komal tells Sooraj that Kabir was seeking forgiveness from her.
 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 suggests telling Komal the truth about Kabir before their marriage if he 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 the 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 their daughter. 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. During the marriage, a boy who is dressed like Kabir claims that he's Kapil, Sooraj's other son, but it is revealed that Mahesh sent the unknown child for some reason.
 The film marked the film debut of Namrata Shirodkar.
 
 
 Jab Pyaar Kisise Hota Hai's music was composed by Jatin–Lalit with lyrics by Anand Bakshi, most of the songs were sung by Lata Mangeshkar, Kumar Sanu, Udit Narayan, Sonu Nigam and Alka Yagnik.
 Mohammad Ali Ikram of Planet Bollywood gave the album 9 stars and stated: "A film which names itself after this immortal tune better have amazing songs. Not to worry, Jatin Lalit deliver a score which is as beautiful as it is melodious, as romantic as it is nostalgic, as simple as it is... In four words, you will love it."
 The film's soundtrack album sold 2 million units in India, making it the ninth top-selling Bollywood music album of 1998.
 A review in India Today noted that the story could potentially have been a "four-hankie tearjerker" but Sareen failed "to deliver". It opined that the "typically over-confident Bollywood brat" Aditya Narayan was the film's biggest problem and it was Khan who "[kept] the film going" quite opposite to Khanna's "awkward hysterics". Concluding the review, it called for her "to take both acting and grooming lessons from mom". Writing for Rediff.com, Dhara Kothari opined that the "storyline [had] been stretched a good deal more than it should have" been. He found the editing weak but noted that Narayan showed "promise". On Khanna's acting, he commented that she exhibited "her limitations" which possibly could be ascribed to her role. He concluded his review by saying that the film "is entertaining enough to draw audiences". Screen magazine wrote it "tackles an unusual subject in an interesting and sensitive manner".
 Khanna told in an interview that scriptwise it was her best film. Aditya Narayan was nominated for the Zee Cine Award for Best Actor in a Supporting Role – Male for his performance in the film.
 The film did quite well at the box office, the film grossed ₹200 million in India and $475,000 overseas for a worldwide total of ₹219.6 million ($5.322 million), against a budget of ₹65 million. It was the eleventh highest-grossing film of 1998.