The theory of Load and Unload Response Ratio (LURR) has applicated in earthquake prediction extensivelly,but it meet challenge also.In this paper,the theory of LURR and its application are analyzed and some aspects for study in near futuer are proposed:(1) Weight of Benioff strain of every small earthquake would be added in LURR calculation according to Coulomb failure stress generated by earth tide; (2) The region shape in where small earthquakes are selected would be determined by the range of LURR would-be-high according to stress distribution before impending large earthquake; (3) By comparing the results of LURR from the assumed same mechanism of small earthquakes and that from measured mechanism of small earthquakes, study the improvement of LURR from using measured data; (4) The applicability of LURR to different seismic fault types of large earthquake would be studied.