This research focuses on how to reengineer Cobol legacy systems into object-oriented systems using Sward's Parameter Based Object Identification (PBOI) methodology. The method is based on relating categories of imperative subprograms to classes written in object-oriented language based on how parameters are handled and shared among them. The input language of PBOI is a canonical form called the generic imperative model (GIM), which is an abstract syntax tree (AST) representation of a simple imperative programming language. The output is another AST, the generic object model (GOM), a generic object oriented language. Conventional languages must be translated into the GIM to use PBOI. The first step in this research is to analyze and classify Cobol constructs. The second step is to develop Refine programs to perform the translation of Cobol programs into the GIM. The third step is to use the PBOI prototype system to transform the imperative model in the GIM into the GOM. The final step is to perform a validation of the objects extracted, analyze the system functionally, and evaluate the PBOI methodology in terms of the case study.