This document specifies the overall framework of ocean hydro-meteorological observation systems, including the system function composition, the data structure type and data transmission format and protocol, as well as the input and output interface. These systems support automatic measurement of e.g. buoy, submersible and shore station instruments, with output interfaces, and provide observations on e.g. water temperature, salinity, depth, current, ocean wave, temperature, pressure, humidity, wind, visibility and precipitation. They have the ability to receive, store, display, process, and analyze data. This document is intended for both developers of ocean observation systems and ocean observers.