Dialysis system is an artificial medical operating system that works as a kidney in the human body, and is used when the kidney has failed or has been spoiled. In this study, reliability and maintainability analysis, which are of the fundamental issues for the operation management of a dialysis system, was developed. Descriptive statistics of all the failures at each device of the system were determined. The failure data covers a period of 45 months. The best fit of the failure data between the common theoretical distributions was found, and the respective parameters were identified. Moreover, the reliability and the maintainability at device and system level for different time intervals were calculated. They both proved to be useful tools to assess the current situation, and to predict reliability, mainly in the short term, for upgrading the operation management of the system. Copyright © 2012 John Wiley & Sons, Ltd.