Abstract:It is needed to make fault sealing boundary of hydrocarbon trap. And it analysis in the region where is an important technique for the fault is the evaluating the hydrocarbon preservation,possible migration path and new reserve exploration stage in oil-bearing region. It will play guiding effect on estimation at optimization management and secondary development of reservoir at development stage. The fault sealing analysis technique consists of 3 fields:1) regional analysis of geophysical and geological data,which will find as much as possible the informations related with the fault sealing analysis (such as lithology,pressure,geochemistry,structural evolution history,and sedimentary environment) and thus help people to determine the sealing and unsealing fault samples of the region and to understand the basic situation of the analysed fault;2) fault surface section will be made to analyse both the concatenation of reservoir lithology on both sides of the fault and the possible lateral hydrocarbon leakage due to the lithology concatenation;3) fault mud rate will be calculated along the fault gone,by determining the threshold value with the use of some constraint conditions,thus to analyse the possible hydrocarbon leakage section along the fault.