Abstract: Since Tianjin Binhai New Area was incorporated in the national development strategy, the construction of this new area has increased the landuse and hence caused considerable environmental problems as a result of large-scale land reclamation with sustainable development of economics and acceleration of urbanization and industrial transfer. In this study, the authors used three hydrogeological sections from the land to the sea to obtain the monitoring data of groundwater dynamic variations and soil salt contents, and discussed the environmental consequences of shallow groundwater in coastal lowland influenced by land reclamation. Overall, three conclusions have been reached: (1) Under the influence of land reclamation, the shallow water level in coastal lowland has gradually increased from the land to the ocean, causing the reverse tilt of groundwater level, which hinders the groundwater run off and drainage; (2) The salt content of topsoil gets higher from the land to the sea, and a large amount of salt is carried from eastern regions to the coastal lowlands, which makes the salinization more serious and wrecks the wetland protection and ecological construction; (3) Land reclamation impact on the ecological environment of the coastal zone is a long slow process, and hence a continuous monitoring mechanism of the ecological environment changes in the coastal lowlands and waters should be set up so as to put forward reasonable suggestions for rehabilitating the ecosystem.