The characteristics of the seismic precursors of hydrogeochemical elements from seismic source and tectonic field in well Liaogu-1 before the Heze M_S5.9 earthquake in 1983,etc.are discussed by analyzing the conditions of structural geology and hydrogeology of the well.Using the knowledges obtained from the theory on fracture displacement and experiment on rock mechanical characters,authors also have probed into the forming mechanism and prediction significance on the seismic precursors of the hydrogeochemical elements from seismic source and tectonic field.The results obtained from the paper enrich the knowledges of seismic precursors from seismic source and tectonic field and are of significance to earthauqke prediction.