Hydrology in the permafrost and seasonal frozen regions becomes the most important segment in the eco-hydrology processes in the cold region, since the water and energy conditions, runoff generation and concentration are changed by the presence of frozen soil. Such understanding is important for regional environmental protection and water management decisions. This paper try to provides an review of research on hydrology in the permafrost and seasonal frozen regions, and introduce the characteristics of the water and heat flow, the peculiar mechanisms of runoff generation and concentration, and the qualities of runoff and water balance in the cold regions.
    Water and heat flow through frozen soil are affected by the formation and presence of ice in the porous matrix in comparison to unfrozen soils. The formation of ice is influenced by soil characteristics, temperature and initial water content, and lead to the diversity of thermal and hydraulic conductivity in the frozen soil, which are need more concern in future research.With respect to frozen ground, its influence on infiltration, percolation and evapotranspiration in both permafrost and seasonal frozen regions result in the clearly distinguishable peculiarities from the hydrology of other geographical zones. Where present, frozen soil acts as a semi-impermeable medium, restricting deep percolation, increasing soil moisture and enhancing runoff in spring. In summertime, the soil water storage capacity in the thawing part of the soil, the depth of which changed over time, controls the runoff characteristics. Excess water at summertime just before soil freezing, which is controlled by the amount of summer rainfall, is stored as ice during winter. This water storage stabilizes the rate of evapotranspiration.
    Besides the introduction of mechanism of hydrology in the permafrost and seasonal frozen regions, some models deal with water and heat transfer processes and hydrological processes are summarized. In the early time, these models used in the cold regions were upbuilt through appending influence of frozen soil to tradition hydrological models, and then some researchers attempt to develop some specialized spatiallydistributed models of runoff generation in the permafrost regions at the present time. However, some the hydrological processes and parameters in these models, which characterized the peculiarities in the cold regions, are still experiential and conceptual.The future research on hydrology in the permafrost and seasonal frozen regions should ravel the mechanisms of runoff generation and concentration on the base of the accessorial data and new technique, develop a cold regions distributed physics-based hydrological model, and quantify the influence on water resource and ecosystem in cold regions.