The "Hungry Ghost Festival" is one of the "Three Yuan" traditional festivals of the Han nationality. "Yuan" means beginning and beginning. The first month of the lunar calendar is the beginning of the year, so it is called January. In ancient times, Erjiazi was regarded as the "Hungry Ghost Festival", which is the fifteenth day of the seventh lunar month (commonly known as "July 15" in the vast southern region). This day is a day for Han people to sacrifice their deceased relatives and remember their ancestors. It is also one of the important "Eight Festivals".

Zhongyuan, Shangyuan and Xiayuan are collectively called "Three Yuans". The Shangyuan Festival falls on the 15th day of the first lunar month (Lantern Festival), the Zhongyuan Festival falls on the 15th day of July (the Zhongyuan Festival), and the Xiayuan Festival falls on the 15th day of October. Along with Qingming Festival and clan, the Ghost Festival is an important manifestation of ancestor worship. It has supported China's development into a secular country and society for two thousand years, while most countries in the world that worship gods have evolved into religious societies.