The present attempt of the author is to acquaint the reader with various theoretical and experimental studies of interest in "Optoelectronic Instrumentation for Research in Oceanography", a topic on which the availability of literature, especially at one place, is very much required for scientists in particular, and researchers and academicians in general, working in this fascinating field. Practically all the important Optoelectronics devices e.g. SATELLITES, SONAR, and MASERS SYSTEMS having applications in Oceanography have been discussed along with the latest research works available in literature.