Aparajita Puja is performed on the last day of the Durga Puja. It is observed on the Dasami day in the Ashwin month. Aparajita Puja 2017 date is September 30. The puja is performed before biding farewell to Goddess Durga. After the puja, the murti of Goddess Durga is taken to a river or lake or sea and immersed.
Aparajita Puja rituals are performed by priests. As the name indicates the rituals glorify the invincible nature of the Mother Goddess. It is also a sort of thanksgiving to her for her victory over Adharma.