The aim of this paper is to obtain a better understanding of the Processes of chloride penetration into hardened concrete exposed to the various zones in marine environements. Chloride content in the concrete is one of the main factors that dictate the initia-tion, magnitude and rate of steel corrosion in concrete. Althou-gh extensive data are available on the chloride content in harde-ned concrete under various marine environments, they are scatte-red in literature, the variables involed are many and there in no unifying approach to correlate this information and formulate a rational basis to explain how the process of chloride contamination develops under marine environments. This research work is the initial stage of a long term study to provide a reali-stic mathematical model for chloride penetration into concrete exposed to real environments.