Abstract: This paper introduces some methods and procedures in building up a Pet-roleum Resource Data File System on WANG-VS-80 mini computer with some examples. Though the computer only possesses a software of data manage-ment system (DMS), a complicated petroleum resource data system can be built up with an extensible multifile structure by adopting certain redun-dant items. The system not only can do the jobs such as retrieving, inqui-ring, updating, revising and deleting geological data but also can do the jobs as petroleum resource estimation, prediction, etc.