Coastal salt marshes are important intertidal ecosystems at the land-ocean interface. While the evolution and behaviour of the salt marsh are affected by various physical and biogeochemical processes, subsurface flow and transport determine the marsh soil condition and material exchange with coastal waters, in particular, it underpins the questions whether marshes export nutrients to coastal water. The soil condition controls biogeochemical reactions and plant growth in the marsh. An important phenomenon in the salt marsh is plant zonation, which has been subjected to numerous studies. Hypotheses have been postulated to link such zonation to water and air-phase flow in the rhizosphere, however, these hypotheses have not been properly testified with little understanding of flow and transport processes in marsh soils. The plant's rhizosphere is within the intertidal zone, which undergoes cycles of immersion and emersion driven by the tides. This leads to dynamic, complex water-air flow patterns and aeration conditions in the marsh soils. Understanding such flow dynamics and aeration conditions is essential for studies of the plant colonization and growth in the marsh. It is indispensable to conduct investigation on complex pore-water flows in marsh soils in order to improve the understanding of these wetland systems, particularly in relation to important hypotheses in the marsh ecology: plant zonation and nutrient outwelling. Such understanding will enhance the ability to preserve and restore salt marsh wetlands. The significance of pore-water flow in salt marshes associated with the important hypotheses, provided an overview on previous researches of field observations and numerical models were discussed in the paper, and more, 4 numerical models (Boussinesq model; 2D saturated model; 2D saturated-unsaturated model; Two-phase, air-water model) used to simulate pore-water flows in salt marshes were discussed. Finally, suggestions on future work were made in the paper. The paper highlighted that hydrodynamics of salt marsh, multi-scale flow research coupled the controlling factors, field observations on creek lognitudinal section and local pore water pressure should be pay attention to. Laboratory experiments and researches on effects of crab burrows are all important to establish fundamental understanding of pore water flow in salt marsh.