Abstract: This paper describes the storage management strategy for the object-oriented database system IDMS. Becauce of the complexity of the data in an object-oriented database system, we adopt the strategy to use relational database management as well as file management system for our IDMS. In a whole, our database management includes class management and object management. Beginning with the database language OOSQL's lexical and semantic analysis, we hive a full description to the two points mentioned above.