Introduction: The prevalence of poor hand hygiene compliance will lead to increase morbidity and mortality and costs .Effective hand hygiene can reduce health care infections. Clinical audit is one of the strategies in quality improvement that could be effect on this issue. Aim: this study was done for evaluation nurses' hand hygiene by clinical audit process. Methods and Materials: this study was pre and post interventional by using clinical audit process that was conducted for 9 months in surgery and internal units in a selective general hospital in Tabriz province in 2013-2014. The target sample was nurses on all shifts. The team who were infection controller, educational supervisor, clinical governance staff and health care management staff were do clinical audit. It was done in six steps identifying problem, finding standards in order to problem, assessment status que ,( pre-audit), comparing status que with standards, generation solutions and implemented and re- auditing (post).Checklists that are designed based on WHO and health minister protocols used. Its validity (CVR=0.85 and CVI=0.80) and reliability (&alpha Chronbach=0.75) assessed. Data were analyzed and by Excel software present. Results: findings showed that total number of situations of pre-intervention was (126) that it increased to (168) situations after clinical audit (post intervention). The total rate of compliance the hand hygiene with standards in pre-intervention was (71.1%) and after the implementation improved (73.59 %.). Conclusion: Process clinical audit have important role to improving hand hygiene standards and for facilitating implementation must be made a team that is consist of all involved staff in its process