The wicked warlord Shan Yu and his Hun warriors invade Ancient China by breaching the Great Wall, prompting the Emperor to order a general mobilization, conscripting one man from every family to fight in the army. Fa Mulan, a young woman with an adventurous personality, goes to the matchmaker in hopes to bring honor to her family, but the meeting goes awry, and Mulan is deemed a disgrace.
Later that evening, Mulan's elderly father Fa Zhou-the only male in the family and retired general-is conscripted to fight, despite Mulan's protests. Fearing for his life, Mulan cuts her hair short, and takes her father's armor and sword, disguising herself as a man and enlisting in his place. After learning of her departure, Mulan's grandmother prays to the family ancestors; the leader of the ancestors decides to send the Stone Dragon to guide Mulan, but Mushu, a pint-sized and sharp-witted dragon and disgraced family guardian, decides to aid her himself.
At the training camp-and with some misguided help from Mushu-Mulan passes her self of as a man called "Fa Ping"; under the command of Captain Li Shang, Mulan and the recruits-including three men called Yao, Ling and Chien Po-gradually become trained warriors. The Emperor's belligerent chancellor, Chi Fu, threatens to dissuade the Emperor from allowing Shang's soldiers from fighting; Mushu then forges a letter from Shang's father, General Li, ordering Shang and his soldiers to meet the imperial army at a town near a mountain pass; when the soldiers arrive, they discover Shan Yu's warriors have burnt down the town and killed General Li's forces.
As they leave, the Chinese soldiers are ambushed by the Huns, and Mulan cleverly uses a cannon to bury Shan Yu's soldiers in an avalanche, but is injured in the fight; while recovering, Mulan's ruse is revealed, and rather than execute her, as the law dictates, Shang, having been saved by Mulan, kicks her out of the army and abandons her in the mountains. Meanwhile, Shan Yu and his surviving warriors follow the Imperial army to the city, and Mulan gives chase.
Mulan enters the city and tries to warn Shang, who refuses to believe her. Shan Yu and the Huns capture the Emperor and barricade themselves in the palace; Mulan, Yao, Ling and Chien Po masquerade as concubines to distract the guards, and allowing Shang to stop Shan Yu from attacking the Emperor; Mulan then lures Shan Yu onto the roof, pinning him down with his own sword; Mushu launches a firework at the Hun leader, and Mulan escapes as he is sent flying into a tower, and incinerated.
The Emperor initially admonishes our heroine, before praising her for saving China, and he and the city's inhabitants bow down to her; she accepts the Imperial crest and Shan Yu's sword as gifts, but turning down his offer to join the Imperial council. Upon returning home, Mulan presents the sword and crest to her father, who states he is just happy to have her home. Having fallen in love with Mulan, Shang is invited to stay for dinner, and Mushu wins his position as guardian back.
