Recent years have brought us face-to-face with various ocean-related problems that demand resolution. Among them are responses to climate change, preservation of biodiversity, management of fishery resources, debris, and underwater noise. One tool that can help solve these problems is “biologging.” Biologging is the practice of attaching devices to animals and recording how they live and information about their environments. The term “biologging” originated in Japan, being coined at the first International Bio-Logging Symposium in Tokyo in 2003. Biologging was defined at the symposium as the “investigation of phenomena in or around free-ranging organisms that are beyond the boundary of our visibility or experience.” This paper discusses possibilities for using marine animals as “observation platforms” in Japan, the characteristics of biologging research undertaken by Japanese researchers thus far, and examples of how biologging in Japan is helping to solve ocean issues. It concludes by considering future prospects for biologging research.