In this paper, Mariko Yoshida offers an ethnographic analysis of temporalities, materialities, and relationalities between humans and oysters in Miyagi, Japan. Yoshida tackles particularly the Pacific oyster, a species endemic to Japan that presently constitutes 80 percent of the total world production of edible oysters. Attentive to the knowledge-making involved in oyster seed production, and the materiality of human-nonhuman relations since the 2011 Tōhoku earthquake, this paper attempts to grapple with the contingent practices that constitute oyster aquaculture in contemporary Japan and the multiple forms of more-than-human entanglements that emerge as a result.