Xu Xian (Chinese: 許仙), courtesy name Hanwen (漢文), is a main character of the Legend of the White Snake, one of China's four great folk tales.

Some legends say that Xu Xian and Bai Suzhen were actually immortals who fell in love and were banished from Heaven because celestial laws forbade their romance.

Lü Dongbin, with a hearty laugh, leads Xu Xian to the bridge, where he playfully turns him upside down, causing him to vomit the tangyuan into the lake.

They have a child together but, their happiness is short-lived when a Buddhist abbot Fahai discovers her true origin, and exposes Bai Suzhen to be a snake.

[3] Xu Xian then spends decades of his life trying to free her, and upon failure becomes monk to stay at the temple, waiting for his wife.