---------------------------------------------------------------------***--------------------------------------------------------------------Abstract Entity Relationship Diagram (ERD) is the first step in database design; it is an important step for the database designers, users, analyst, and managers and in software engineering. In this paper, a methodology for detection of ambiguity in the ERD diagram is given. If ambiguity is found then apply various normalization techniques to remove it. The Normalization algorithms that are included are – 1NF, 2NF. This methodology is based on a predefined set of a heuristic rules that aims to extract the ambiguity of the ERD, then these rules are mapped into a database. A diagram generator automatically converts ERD into database schema's or table according to the rules of generations. The proposed methodology is explained by the examples to show how it can provide a mechanism for quick and easy way in extracting the Database Schemas.