Introduction: Health Care organizations, because of their special nature of Medical Services, impossibility of assessment by customers, and increasing of patients and customer expectation, have to apply different management approach. In recent decade Six Sigma has been considered as systematic and powerful to improve service quality and cost saving. Six Sigma is a statistical and systematic approach that tends to define the process performance defects and decrease the clinical and business processes errors that are done with wasting time, high costs and poor outcomes. The aim of this paper is to investigate the role of Six Sigma on the improvement of quality services in Health Care Organizations using library and internet resources, and descriptive and analytical methods.

Literature review: Empirical Results in different countries that have through implemented Six Sigma in Health Care Organizations have improved the time cycle and patient cycle in emergency room, operating room, radiology and laboratory services, supportive management, antibiotics treatment, improvement in scheduling hospital staff activities, medical errors and cost saving. Also, good infrastructure and continual training is a must to six sigma implementation. 

Conclusion: Six Sigma methodologies provide a systematic approach to improvement business processes based on customer demand and actual analysis in carrying out processes in any organization. There is a major difference between Six Sigma and other approaches and that is why it is being used in Health care organizations. Nevertheless the different methods used to implement whatever approach the basic ground to embrace the culture quality should exist in the organization, Also quality improvement is a continuum process which derives the cooperation of all working teams and the use of appropriate means and methods in solving individual problem. Although, the use of any method needs to preparation and adaptation of quality culture in organizations. Also quality improvement is continuum process that needs to cooperate and interaction among work teams and use of suitable tools and methods for any problem.