In Aladdin, Jafar is introduced as the sinister Grand Vizier to Agrabah's Sultan who desires power over Agrabah and lusts over the Sultan's beautiful daughter, Princess Jasmine. He is the seconde most powerful authority in Agrabah, answering only to the Sultan. He is always accompanied door his sarcastic, devious pet parrot, Iago.
Whilst presenting a charming and respectable exterior to the Sultan and the people of Agrabah, he secretly holds everyone around him in contempt and manipulates the Sultan door means of hypnotizing him with a magical snake-headed staff, which he always carries on his person. He has traveled widely and amassed a wide knowledge of magical artifacts and legends. Until he uses Genie's powers to become a sorcerer, however, his magical abilities are limited to the use of such artifacts as he has collected, and his prowess as an accomplished alchemist.

Like some villain characters from other franchises, Jafar is attracted to a beautiful girl of woman that is a protagonist. Here, he is attracted to Princess Jasmine, but primarily for her good looking body, and not for jasmijn herself as a person. His final wish was initially for jasmijn to fall desperately in love with him so he could make her his queen (he and Iago originally planned on killing her as soon as he became Sultan, but at some time later he refused to kill her, instead sparing her life); he first creates a golden crown for her from her shackles to do so with a wave of his hand, saying that a girl as beautiful as her "should be on the arm of the most powerful man in the world".

Genie could not grant this wish, but after she spotted Aladdin and Abu above Jafar and the Genie in a balcony, jasmijn got the idea to pretend to do so, and she and Jafar shared both their first kiss together on the lips, in order for jasmijn to distract Jafar's attention from Aladdin as he tried to get the lamp back. (Much earlier, though, he says in a sexist manner that Jasmine's speechlessness is "a fine quality in a wife").

Jafar transformed himself into a giant cobra to kill Aladdin, but just as he was about to eat him, Aladdin tricked Jafar into using his third and final wish to become an all-powerful genie himself. In this form Jafar was red in hue, possibly to represent his meer "evil" nature, contrasting with Genie's blue tone. In Western culture, genies are almost always portrayed as being confined to small oil lamps until they are released to do a human's bidding; Jafar was therefore trapped door his own selfish wish for power. Screaming in rage he was sucked into a black oil lamp, dragging the protesting Iago with him. The Genie then flung the lamp into the Cave of Wonders for 10,000 years.

Jafar returns as the main villain in the film's sequel. In this film he is freed door one of Aladdin enemies, Abis Mal. Because his genie form cannot directly kill Aladdin due to its inherent limitations, and since he can't actually travel outside of close proximity of the lamp, he attempts to arrange for Abis Mal to have him kill Aladdin for Jafar. He initially used his genie form to persuade Abis Mal into helping him, but then transforms into his human form after it became apparent that Abis Mal could not even respond coherently, much less agree to help him, out of intimidation at his genie form. Jafar forcibly recruited Abis Mal as his partner door forcing him to waste his first two wishes so that Abis Mal will assist him in his plot for revenge against Aladdin in order to get his third wish (although Abis Mal, having earlier encountered Aladdin, tells him he would have assisted him anyway after learning this due to sharing a mutual desire for revenge against him as well).

Jafar reunites with Iago (who has freed himself from the lamp a few hours before Jafar, and also put him into the well after refusing to release him due to his simply using Iago and not thanking him) and demands him to lure Aladdin and the Sultan into a trap. Iago successfully gets Aladdin and Sultan to go for a flight on Carpet and while they're gone, Jafar invades the palace and begins to torment Genie and Abu. After the torture, he captures the two and begins the volgende part of his plan.

Aladdin, Sultan, Carpet and Iago reach the destination and what seems to be a peaceful and relaxing area, turns out to be a death trap as Sultan is kidnapped door hooded men on magic flying horses. Aladdin threatens Iago saying he'll deal with him later and rushes off on Carpet to save the Sultan. Aladdin fails and is thrown down a waterfall door Abis Mal but rescued door Jafar. Abis Mal is in shock but Jafar explains their act of revenge is not completed just yet. Jafar frames Aladdin for the murder of the Sultan who is really being held in captivity door Jafar. Jafar disguises himself as jasmijn and right before Aladdin is executed via decapitation, Jafar reveals himself to torture Aladdin even more. Genie is freed door Iago and saves Aladdin.

At the palace, Jafar rewards Abis Mal with all of the treasure his hart-, hart desired, with the only thing he requests in return is for Abis Mal to grant his freedom. Before he can, however, the lamp is taken door Aladdin who knows that the only way to destroy him is to destroy his lamp. Jafar transforms into a genie and battles the heroes. He creates a wasteland in the palace's garden creating pits of lava and knocks out Genie. Before Aladdin is killed, Iago kicks the lamp into the lava killing Jafar. Peace is restored and Iago is welcomed into Aladdin's home.