Ice flood during thawing period in the Ningxia-Inner Mongolia reach of Yellow river is concentrated in mid and late March.and usually make up from ice melting flood and ice dam flood. Its characteristics primarily shows the large annual change of ice flood peak and flood volume, obvious increase of that along the river; being easy formation of multi-peak at Toudaoguai station; the ice flood peak coefficient in march being smaller than that in summer, shorter duration compared with summer flood, higher water level of the same discharge than that in summer and slower velocity of runoff in rising segment than that in falling segment. These characteristics principally relate to the river morphology, water conservancy projects, freeze-up period upstream inflow, air temperature in thawing period, river thawing situation, freeze-up period river channel-storage increment volume, along distribution and its release degree.