Maintenance of  hospital buildings and its management are regarded as an important subject which needs attention because hospital buildings are service institutions which are very important to a society, requiring the search for the best procedure to develop maintenance in hospitals. The research is aimed to determine an equation to estimate the annual maintenance cost for public hospital. To achieve this aim, Al-Sader City Hospital maintenance system in Al-Najaf province has been studied with its main elements through survey of data, records and reports relating to maintenance during the years of the study 2008-2014 and to identify the strengths, weaknesses, opportunities and threat points in the current system through Swat analysis, which represents " analyzing the internal factors represented by strengths and weaknesses points and the external factors represented by opportunities and threats," [41]. On the basis of that, an equation has been obtained to estimate the cost of annual maintenance. To achieve this aim, the following issues should be taken into consideration:
 
 Studying the actual work program of the maintenance department in  Al-Sader Hospital,
 Identifying the procedures used in maintenance and ways they are implemented,
 Studying the maintenance records and reports,
 Holding interviews with the manager of maintenance and its staff to integrate the information and
 Integrating the analysis of maintenance cost by using statistical analysis system (ASA 2012).

To assess the validity of the model for the annual maintenance cost, the predicted values of the . equation are plotted against the actual measured (observed) values. Based on the validation data set, the coefficient of determination (R) was found to be equal to (82.5%), therefore it can be concluded that the developed equation showed moderate agreement with the actual measurements. Finally, it can be concluded from the study that, the developed equation should be  pplied in hospital to overcome the problems and weak points of the current system and to estimate the annual maintenance cost for hospitals based on the scientific method.