In this paper.analysis is made on the law of variation of river stage of ice jam in freezing periods,re-lation between stage variation and evolution of ice jam is discussed and a,relational expression of pnrameter is es-tablished on the law of variation of river stage based on the data observed in the Hequ Reach of the Yellow River-According to the field observation research.study has been made on the simulated ice jam stage in the lab.The icejam stage is the same as that in the natural river Therefore,the relational expression of the parameter can be used to calculate and forecast the ice jam stage.