Conan the barbarian is a film about a young savage who avenges his tragic parents. The story takes place in a fictional barbaric era thousands of years before the rise of modern civilization. At the beginning of the film, friedrich nietzsche's famous saying was paraphrased: "Those who don't kill us will make us stronger. Next, there is a voice-over commentary behind the black background, indicating that the film tells the origin of Conan. Drums and trumpets were accompanied by the forging of a sword, and then the camera turned to a mountain top. The sword maker told his youngest son Conan Steel about the mysterious mystery of the importance of metals to Merrians. Then, the village of Smolian was slaughtered by a group of warriors led by Tulsa Dum. Conan's father was killed by a dog, and his sword was snatched by Dum to behead Conan's mother. All the children became slaves. Conan was locked in a big mill called "Wheel of Pain". After years of pushing this huge mill, he grew strong muscles. He was sold to a new owner and trained as a gladiator. After many victories, Conan was finally released. After he regained his freedom, he escaped into an ancient tomb because he was chased by some wild dogs. In the ancient tomb, he saw the body and sword of a general, so he took the sword and went on his way again. Conan, who roams the world, meets a young witch and has sex with her in exchange for guidance. However, halfway through, the witch suddenly turned into a demon, and Conan could only repel it. Conan also met Sue on the road. He is an archer, but he is also a thief.

At the suggestion of the witch, Conan and Sue went to Shadizar in Zamora to look for Dam. They met a female robber named Valeria. The three of them sneaked into the "Snake Tower", a cult temple dedicated to snakes in Dum, and stole huge snake eyes made of precious stones and other valuables. Conan and Sue also fought with a big snake and killed it. After escaping with stolen goods, the three celebrated and got drunk. The city guards caught them and brought them to King osric. The king asked them to rescue their daughter who joined Damme. Sue and Valeria didn't want to get involved in this muddy water, but Conan went to each other's temple alone with a deep hatred for Dum.

Conan disguised as a priest sneaked into the temple, but was found, captured and tortured. Dum preached his great strength to him and proved it by persuading a girl to commit suicide. Then he ordered Conan to be crucified on the "Tree of Disaster". When Sue found him, Conan was dying. Sue took him to the tomb where Conan got the sword before, where a wizard lived. The wizard summoned ghosts to heal Conan and warned them that they would "pay a heavy price" for it. Valeria accepted this condition. These ghosts also tried to kidnap Conan, but Valeria and Su Taibo repelled him and Conan recovered. This time, Sue and Valeria agreed to the king's request and sneaked into Dum's temple with Conan. Because the cult was indulging in a cannibalism carnival, the three men took advantage of the chaos to attack and fled with the princess, while Valeria was seriously injured because she was hit by a dum-dum bullet. Just like the "heavy price" predicted by the wizard before, she died in Conan's arms and was cremated in the ancient tomb. Conan, Sue and the guide are then ready to launch a decisive battle against Dam. They used trap tactics and terrain to kill Dam's guards. Valeria also appeared in the battle as Valkyria, saving Conan's life again. Conan also found his father's sword, but the blade was broken. Damm, who lost the protection of the guards, attacked the princess with a poisonous snake. After being stopped by Sue, he escaped from the temple.

Conan sneaked back to the temple, and Dum was standing at the top of the stairs giving a speech to cult members. Dum rushed forward to try to hypnotize Conan, but Conan successfully resisted hypnosis and cut off the enemy's head with his father's sword. Then Conan set fire to the temple and sent the princess back to the king's castle. The last scene of the film shows that he has become an old king, and the explanation in the background shows that he is enthroned in another story.