Patient's master data is an important data for hospital's operational. If the master data quality does not meet the expectation, it will affect the billing process and then will affect the income for the hospital. Master data management can help the hospital to integrate all their master data they have so for each data there will be only single source of truth and validity of data will be complied. By doing assessment of master data management maturity, hospital will be able to identify what aspect of master data management that they lack so the process can be improved as well as the quality of master data. Assessment of master data management maturity level is done using Master Data Management Maturity Model (MD3M) by Spruitz and Pietzka. The assessment showed 90 percent of activity related to master data management has been implemented. Some policies need to be implemented regarding to the master data management, such as documentation of the policies and the definition of master data, formal appointment of the data stewards, and the implementation of master data quality management.