The ERP Software maintenance was identified as an integral part of a software life cycle that plays an important role in ERP software products to alleviate problems. The planning activities for example; personnel’s, cost, documentation and support is necessary to facilitate maintainability define by various qualities as analyzability, changeability, stability, and testability. The maintenance is conducted after released of the product to detect errors, correct them to improve its performance and to adapt changes in environment. The ISO14764 categorizes both the perfective as well as adaptive maintenance to be enhancements while preventive and corrective maintenance as corrections. The software maintenance activities and task are performed by maintainers. The enterprise architecture models in system maintainability and extended influence diagrams were used to analyses attribute that influenced maintainability. The quality models as ISO 9126, Boehm, and McCall explored to show key attributes of maintainability. The existing standards models use to define the process of ERP software maintenance included IEEE Standard 1219-1998 and ISO/IEC 12207. The software maturity index was describe as methods used to measure the software maintainability involving combination of characteristics measures such as source code readability, quality of documentation and software understandability. The integrated approach model suggested which incorporates the various measures of software maintainability is the fuzzy model which considers the three extents of source code readability, quality of documentation and software understandability. The ERP software maintenance tools discussed include program comprehension and reverse engineering tools; Software Testing Tools and software configuration and management tools. The various issues were identified during ERP software maintenance such as maintenance cost, limited understanding, and quality of product, impact/work analysis, maintenance staff experience, process issues and outsourcing. A number of ways suggested solutions to ERP software maintenance issues: testing quality; understandability; software reengineering; Bugs elimination; reduce complexity; re-documentation; dead code removal and software refactoring.