There is only traditional Dulong festival, namely the New Year, "Ka'erjiangwa" in the Dulong language. It is held after the autumn harvest, usually from December to the next January. Both the date and duration are uncertain.

The New Year is usually held in a large family or a village, the date fixed beforehand. At that time, every family would invite friends to celebrate together, oral messages for those nearby, and knotted ropes or carved boards as "invitation" for those living far away. The day before the festival, they must prepare wine, meat, rice and "Lada'er", which is a bamboo with a new flax blanket on it. The number of the blankets should accord with that of the family, or there can be more blankets, but never less. In their opinion, more blankets foresee a larger population of family members and the cattle, while fewer blankets are ominous.

The New Year of Dulong people is both a celebration of the harvest and a ceremony of offering. Therefore, one of the most important activities on that day is butchering a bull and offering it to the god of "Gemeng" and other gods. "Gemeng" is the ancestor of the human being in Dulong mythology, who created man. Dulong people believe, that by butchering a bull to offer to him, they can get his blessing and protection from disasters and diseases, and the weather of the next year will be fine enough to ensure a good harvest.

The ceremony is presided by a shaman. At the beginning of the ceremony, a bull wrapped in a Dulong blanket is brought into the field, and its halter fastened to a big pole. People form circles around the bull, and commence dancing, swinging swords and spears, in the sound of mang luo (a music instrument). When the other offerings are ready, the shaman burns the incense, and murmurs some words, praying to Gemeng for safety of both people and the cattle, and everything being well off. Then he stabs a sharp bamboo spear under its arm, and the bull is butchered and died. They cook the beef and eat together. The shaman still has to carry the head on his back, and lead all the people to dance around the offering bull. At this moment, the atmosphere of New Year has got its climax. People are drinking and eating, singing and dancing. The bank of the Dulong River is filled with joy and laughter.