Because of the low quality of data provided by information systems such as data missing, data conflicts and data duplicate, it is widespread in enterprise that decision-makers are often faced with “rich data but poor information”. To improve the data availability of information systems, the main factors affecting data quality of relational database are studied in this paper, also a unified metadata model based on multi data sources and a data quality assessment model are proposed, and a set of interactive visual analogues for data quality assessment is built. Finally, a visual analysis system for data quality in relational database is developed, which is verified with several enterprise practical cases. It is indicated that the built system can analyze data quality effectively, and then improve the reliability and accuracy of enterprise decision-making.