The story was set far in the distant past, when the common people of the Tibetan plateau were subjected to natural disasters and calamities across their lands. Demons and spirits run wild. The Goddess of Mercy, in the hope of helping the people, asked the Amitabha Buddha to send the son of the God of Heaven to the world to defeat the evil demons.

Toiba Gawa, who later came to be known by the name Gesar, descended to the earth and became the king of the Tibetan people. Able to defeat the demons, aid the poor and benefit the common people, Gesar is portrayed as a combination of god, dragon and a fierce spirit known as nyan in Tibetan primitive religion. He was endowed with special characteristics and marvelous powers and abilities. Gesar suffered several trials. However, his invincible power and the protection of the God of Heaven allowed him to survived and eventually defeat the evil demons.

Throughout his life as a human, he worked to rid the common people of the scourges of their existence. At the age of five, he moved with his mother to the banks of the Yellow River. When he was eight, they were joined by the members of the Ling tribe. Winning a horse race against the finest warriors of the tribe at the tender age of 12, he was recognized as the chief of the tribe. He married Sengjam Zholmo. Gesar then led expeditions against the enemies of his tribal kingdom. He defeated the northern demons that had invaded the lands of the Ling Kingdom. In successive campaigns, he defeated King Gurdkar of the Hor Kingdom, King Sadam of the Jang Kingdom, King Shingkhri of Monyul, King Nor of Tangzig, King Chidan of Khachevigyu, King Toigui of the Zugu Kingdom and scores of small tribes and minor kingdoms known as zongs in ancient Tibet. After completing his sacred mission, he returned to heaven together with his mother and wife, bringing to a dramatic close the grand epic of his life.

The story's structure touches upon two important periods in Tibetan social development and includes depictions of almost 100 tribes, kingdoms and regions. The epic is generally divided into three parts: the birth of Gesar; the expeditions against the enemies; and his return to heaven. Of the three parts, the depictions of his battles and exploits are the most detailed and contain the most enlightening materials in relation to Tibetan history and culture. The second part includes four parts-Defeating Demons in the North, Battles Between Hor and Ling, Defend the Salt Sea, and Battles Between Mon and Ling--as well as battles to conquer 54 zongs.