The main festival of Lanh Giang Temple is held from the annual 1st to the 4th day of the Sixth lunisolar month. The main festival lasts for four days on the official schedule and it is not until the 25th of June when the closing ceremony takes place.

The hagiography book preserved at the temple goes that the 25th of August in the Year of the Fire Tiger is the ascension day of Pham Vinh (the deity worshiped at Lanh Giang Temple). The Hagiography written on the ancient royal decree also clearly states: “Date of birth: the 10th day of the first month of the lunar calendar, offerings: vegetarian food for the upper rituals, pork for the lower rituals. Day of ascension: the 25th day of the eighth month of the lunar calendar, offerings include buffalo and cow meat, sticky rice, and wine.” Currently, the temple does not organize the festival in the lunisolar Eighth month but on the 25th the month, the Management Board of the Relic and the temple still conduct ceremonies for the saint and welcome people from other places to visit and celebrate.