There once was a young, poor, but kind-hearted cowherd called Niulang, and an old ox. The ox actually was once the god of cattle, but downgraded as he had violated the law of heaven. Niulang once saved the ox when it was sick. In order to show its gratitude, the old ox helped Niulang get acquainted with Zhinü (a fairy, the seventh daughter of a goddess and the Jade Emperor) when she escaped from her boring life in heaven to look for fun on earth.
Zhinü soon fell in love with Niulang and they got married without the knowledge of the goddess. Niulang and Zhinü lived a happy life together; Niulang worked in the field while Zhinü did weaving at home. After a few years passed, they had two children, one boy and one girl.
However, the Goddess of Heaven (Zhinü’s mother) found out that Zhinü, a fairy girl, had married a mere mortal. The goddess was furious and sent celestial soldiers to bring Zhinü back. Niulang was very upset when he found his wife was taken back to heaven. Then his ox asked Niulang to kill it and put on its hide, so he would be able to go up to heaven to find his wife. Crying bitterly, he killed the ox, put on the skin, and carried his two beloved children off to heaven to find Zhinü.
Just before he caught up with Zhinü the goddess of heaven took out her hairpin and created a huge river between them, and they were separated forever by the river that later became known as the Milky Way.
Heartbroken, he and his children could only weep bitterly. However, their love moved all the magpies to take pity on them, and they flew up into heaven to form a bridge over the river, so Niulang and Zhinü could meet on the magpie bridge. The goddess was also moved by their love, so she allowed them a meeting on the magpie bridge on that day every year (the seventh day of the seventh lunar month).