This Descriptive-correlational study aimed to provide a model to predict organizational performance based on unlearning and by considering the mediating role of intellectual capital. The study population consisted of all employees of Sports and Youth Departments of Iran, among whom 384 people using the Korjsi and Morgan table were selected with stratified random sampling sampling method. The data were collected using paper and electronic questionnaires and analyzed in AMOS using the structural equation modeling (SEM) method. The reliability of the Unlearning Questionnaire (Navarro and Polo, 2008), Intellectual Capital Questionnaire of Bontis (1998) and Organizational Performance Questionnaire (Winand et al., 2014) was confirmed with Cronbach’s alpha values of 0.83, 0.96 and 0.97, respectively. The proposed model fitted the data well; thus, the path coefficients were all significant. Unlearning had significant positive effects on organizational performance through intellectual capital. In addition, unlearning had the largest impact (0.96%) on intellectual capital than on other research variables. Therefore, managers of Sports and Youth Departments of Iran are recommended to adopt unlearning strategies in the workplace to replace employees’ old knowledge with new knowledge, and thereby increase intellectual capital in the desired organizations. This will help organizations to improve their performance in today’s ever-changing environment.