The Ghost Festival or Hungry Ghost Festival, also known as the Zhongyuan Festival in Taoism and the Yulanpen Festival in Buddhism, is a traditional festival held in certain East and Southeast Asian countries. According to the traditional Chinese lunisolar calendar, the Ghost Festival is on the 15th night of the seventh month (14th in parts of southern China).

In Chinese culture, the fifteenth day of the seventh month in the traditional Chinese calendar is called Ghost Day or (especially in Taiwan) Pudu (Chinese: 普渡; pinyin: Pǔdù; Pe̍h-ōe-jī: Phó͘-tō͘) and the seventh month is generally regarded as the Ghost Month, in which ghosts and spirits, including those of deceased ancestors, come out from the lower realm (diyu or preta). Distinct from both the Qingming Festival (or Tomb Sweeping Day, in spring) and Double Ninth Festival (in autumn) in which living descendants pay homage to their deceased ancestors, during Ghost Festival, the deceased are believed to visit the living.

On the fifteenth day the realms of Heaven and Hell and the realm of the living are open, and both Taoists and Buddhists would perform rituals to transmute and absolve the sufferings of the deceased. Intrinsic to the Ghost Month is veneration of the dead, where traditionally the filial piety of descendants extends to their ancestors even after their deaths. Activities during the month would include preparing ritualistic food offerings, burning incense, and burning joss paper, a papier-mâché form of material items such as clothes, gold, and other fine goods for the visiting spirits of the ancestors. Elaborate meals (often vegetarian) would be served with empty seats for each of the deceased in the family, treating the deceased as if they are still living. Ancestor worship is what distinguishes Qingming Festival from Ghost Festival, because the latter includes paying respects to all deceased, including the same and younger generations, while the former only includes older generations. Other festivities may include buying and releasing miniature paper boats and lanterns on water, which signifies giving directions to the lost ghosts and spirits of the ancestors and other deities.

The name relates to the concept of the hungry ghost, the Chinese translation of the term preta in Buddhism. It plays a role in Chinese Buddhism and Taoism as well as in Chinese folk religion, and represents beings who were originally living people, who have died, and who are driven by intense emotional needs in an animalistic way.

As a Taoist festival: Taoism has the "Three Yuan" theory (representing the Three Great Emperor-Officials), which the name "Zhong Yuan" comes from. The festival flourished during the Tang dynasty, whose rulers were partial to Taoism; and "Zhongyuan" became well established as the holiday's name.

As a Buddhist festival: The origin story of the modern Ghost Festival, ultimately originated from ancient India, deriving from the Mahayana scripture known as the Yulanpen or Ullambana Sutra. The sutra records the time when Maudgalyāyana achieves abhijñā and uses his newfound powers to search for his deceased parents. Maudgalyayana discovers that his deceased mother was reborn into the preta or hungry ghost realm. She was in a wasted condition and Maudgalyayana tried to help her by giving her a bowl of rice. Unfortunately as a preta, she was unable to eat the rice as it was transformed into burning coal. Maudgalyayana then asks the Buddha to help him; whereupon Buddha explains how one is able to assist one's current parents and deceased parents in this life and in one's past seven lives by willingly offering food, etc., to the sangha or monastic community during Pravarana (the end of the monsoon season or vassa), which usually occurs on the 15th day of the seventh month whereby the monastic community transfers the merits to the deceased parents, etc.,

The Theravadan forms of the festival in South and Southeast Asia (including Cambodia's Pchum Ben) are much older, deriving from the Petavatthu, a scripture in the Pali Canon that probably dates to the 3rd century BC. The Petavatthu account is broadly similar to that later recorded in the Yulanpen Sutra, although it concerns the disciple Sāriputta and his family rather than Moggallāna.

The Ghost Festival is held during the seventh month of the Chinese calendar. It also falls at the same time as a full moon, the new season, the fall harvest, the peak of Buddhist monastic asceticism, the rebirth of ancestors, and the assembly of the local community. During this month, the gates of hell are opened up and ghosts are free to roam the earth where they seek food and entertainment. These ghosts are believed to be spirits of those without descendants (or, traditionally, without descendants in the male line) or whose descendants did not pay tribute to them after they died. They are desperately hungry, thirsty, and restless as a result. Family members offer food and drink to the ghosts and burn hell bank notes and other forms of joss paper. Joss paper items are believed to have value in the afterlife, considered to be very similar in some aspects to the material world. Families pay tribute to wandering ghosts of strangers so that these homeless souls do not intrude on their lives and bring misfortune. A large feast is held for the ghosts on the day of the ghost festival or thereabouts, when people bring samples of food and place them on an altar or outside a temple or house, to please the ghosts and ward off bad luck. Lotus-shaped lanterns are lit and set afloat in rivers to symbolically guide lost souls to the afterlife.