Indonesia, as a maritime country with an ocean area that is much larger than its land area, requires special courses that discuss issues related to the knowledge and utilization of Indonesia‘s marine resources. The approach taken in this lecture is phenomenology with the focus of discussion emphasizing aspects of marine physics. Discussion topics in lectures include: physical properties of sea water; waves and ocean energy; tides and ocean currents; regional and global ocean circulation; Indonesia‘s geographical position and The Indonesian Through-Flow (ITF), a hydro-meteorological disaster related to the hydrological cycle of sea water and the characteristics of tsunami waves.