The current study was conducted to investigate the effect of internal marketing on organization-based self-esteem at Isfahan University of Medical Sciences. The relationship among internal marketing components (payments, managerial styles, environment of the organization and employee participation) with organization-based self-esteem was investigated. Standard internal marketing questionnaire by Ahmed and Rafiq (1993) which has twenty three questions and Pierce and Gardner's organization-based self-esteem questionnaire with ten questions were tools of data collection. The study was conducted using descriptivefield method. The statistical population included five hundred employees of Isfahan University of Medical Sciences among whom one-hundred fifty four persons were selected through stratified random sampling method. Opinions of experts as well as confirmatory factor analysis were used to confirm content validity and face validity. The results indicated confirmation of the questionnaire. In order to ascertain the reliability, Cronbach's alpha coefficient was applied that was obtained equal to 0.95 and 0.90 respectively for internal marketing and organizationbased self-esteem. A significant relationship was obtained between internal marketing (payments, managerial styles, environment of the organization and employee participation) and organization-based self-esteem using statistical tests such as Kolmogoroff-Smirnoff test, factorial analysis and structural equations modeling. The results revealed that whatever