Abstract: In 1988 the IGCP Project No. 269 was established to examine the feasibility of global databases in sedimentary petrology by constructing a prototype database. The database is com-posed of variety of analytical values in sedimentary rocks and sample specification data. Avail-ability on personal computers are essential for the project so that it can be used also in develop-ing countries. Regional groups were established to collect data,because it is often difficult for re-searchers outside the region to get information on data sources. A logical unit corresponds to a specimen,and it is composed of a header block and an intrinsic block. The format of the header block is common for all types of sedimentary rocks,but that of the intrinsic block differs for each rock type. Many problems were resolved,not only technical problems in information pro-cessing,but also theoretical problems in sedimentology. The database management systems,in-cluding retrieval and analytical functions were developed by using several commercial softwares. The prototype database with more than 400 sample data was developed and distributed for ex-amination by sedimentologists in the world. The actual database,which contains a large amount of global data,is now under development,and it will be integrated into a kind of knowledge base for sedimentologists as a useful tool for studying sedimentary facies,province,environment,and so on.