: This article aims to describe and analyze critically about the ritual of khanduri laôt in lowland Aceh. This annual ritual has been performed from one generation to another for it cannot be separated from the life of fishermen and it leaves a deep impression among the participants. This research is a field research and its data is obtained through meticulous observation of the ritual action and in-deep interview, discussion with the main protagonists of the ritual performance. The result of the research shows that the village fishermen made the offering (cosmological exchange) besides reciting the verses from the Qur'an. The offering is made to “the possessor of the fish” and is also given to “the sea water spirit” who takes care of the fish pond, the coast sea, the sea's surface, the waves, and the deep sea. The village fishermen considered that cosmological exchange is important to be done as the protection for the fishermen from harm at sea besides the fish will go near the sea coast and taste the khanduri so that the fishermen can easily catch them.