The Laba Festival falls on the eighth day of the twelfth lunar month. This holiday may be traced back to the ancient Chinese custom of sacrificing game to the ancestors during the last month of the lunar year.

Eating porridge on the Laba Festival is a very old tradition. As Buddhism became integrated into Chinese society, "Laba porridge" became known as "Buddha porridge," in commemoration of the date of Buddha's enlightenment. Legend has it that after Sakyamuni left secular life to become a monk, he meditated so deeply that he often forgot to eat. Once, when he was close to dying of starvation, he encountered a woman tending her flock. The woman saved his life by feeding him rice porridge with milk, enabling him to continue meditating and attain enlightenment on the day of Laba Festival. In order to commemorate this incident, every year at the Laba Festival Buddhists eat Laba porridge, also known as Buddha porridge. Many versions of the legends concerning the origins of Laba Festival exist in different regions of China.

The two most important traditions associated with Laba Festival are eating Laba porridge, and praying for peace and good health in the coming year.