This festival symbolizes the Descent of Buddha from the heaven of the thirty three gods after visiting his mother. `Dhuechen` means festival, `Lha` means heaven and `Bab` means descent.

Legend says that Queen Maha Maya, the mother of Lord Buddha, did not live long after his birth and took rebirth in Trayastrimsa or the heaven of the thirty Gods. After attaining Enlightenment, Lord Buddha came to know about the whereabouts of his mother through spiritual powers and at the age of forty-one ascended to the heavens along with thousands of his followers. Lord Buddha stayed in heaven for three months during which he delivered sermons to his mother and other celestial beings. Lord Buddha had left one of his disciples behind on earth. The name of the disciple was Maudgalyayana and he was his representative. This disciple and other devotees of the Lord could not bear the long separation and longed to hear his preaching. Maudgalyayana, who possessed miraculous powers, was exhorted to go up to the heaven to request the Lord to return back to the earth. The gods were not willing to let Lord Buddha return back to earth but Maudgalyayana suggested that as the earthly beings did not have the powers to visit heaven, the celestial beings could come to the earth to attend his preaching. Lord Buddha finally relented and descended to the earth at a place called Sankasya along a triple ladder that was prepared by Viswakarma, the God of Machines.