The development and distribution of mangrove forests vary depending on both biotic and abiotic factors. Differences in structure and function of mangroves are reflected in differences in their environmental setting, including their hydrological regime. However, the influence of hydrology on the mangrove forests of Vietnam has received little scientific attention, therefore the purpose of Effect of Hydrology on Mangrove Ecosystems was to determine the effects of hydrology on specific structural attributes and functional processes within the mangrove ecosystems of Can Gio district, HCM City in southeastern Vietnam. This research addressed adressed the following questions: What are the characteristics of the hydrological regime at the Can Gio mangrove forest? And how does the hydrological regime in the Can Gio mangrove forest affect soil properties, sedimentation, litter decomposition, primary production and species distribution?