Taking place during in the 2nd to 3rd lunar month, the festival derives from the cult of worshipping whale, also known as Ông Nam Hải (Mr. Nam Hải). Whale worship is a longstanding tradition of maritime communities along the Central coast. According legend and local belief, whales are savior of fishermen in the sea and bring about good fisheries. In Khanh Hoa Province, the festival begins with a Nghinh Ông (Whale Procession) Ceremony in the sea. To invite the whale spirit, the local fishermen make an offering ceremony on the sea. After that, 15 fishing boats, lining up in a V shape, make a parade on the sea, processing the whale’s spirit to his temple on shore. The festival subsequently continues with the royal decree procession ceremony. This is followed by a ritual inviting the spirit enter the temple. Lion and dragon dances, bá trạo singing and tuồng opera performances add a more joyful atmosphere into the festival.

Held from August 15 to 17 at Ong Thuy General's mausoleum to commemorate the merits of "Mr" fish - the god who patronizes fisheries and marine occupations in general. On the 16th, at Lang Ong, a procession was held to process the South Sea General's palanquin onto the dragon boat to the sea. Along with the dragon boat carrying the water general, there were hundreds of large and small boats, splendidly decorated, with colorful flags and flowers accompanying him to the sea to welcome him. In front of the boat are incense and offering trays. On these large and small boats, there are thousands of tourists and relatives participating in the procession. When the Spirit is brought into the mausoleum, the ceremonies of praying for peace, building adoration of the great boi, and singing boi take place at the mausoleum of Mr. Thuy General. On the 17th, there was a ceremony to honor the king of Thuy Prime by ordination. The worshiping ceremony includes singing.