Abstract: In combination with lithological characters of crevice reservoir in the burial hill pool of dense oil,the motion pat- tern of bottom water in X1 block is analyzed,and the com- patibility between the grain size of blockage agent and the o- pening of reservoir crevice is studied.The composite applica- tion of grain and gelatin blockage agent and blockage tech- niques as single blockage,double- section blockage and three- section blockage of high dose are selected to plug off bottom water.Since 2002,the annual output of crude oil has been raised,the overall water content has decreased in suc- cessive three years after the application of the composite techniques for 135 times.The laboratory tests and the appli- cation effect show that the suggested matching blockage technique can meet the need of blockage for the dense oil pool with abundant bottom water and crevices.