Since reference practices influence Journal Impact Factor (JIF), Author Self- Citation (ASC), number of times an author cites herself / himself, andJournal Self-Citation (JSC), number of times the journal cites itself, as a portion of total citations should be considered in citation analysis. ISIprovides quantitative indicators for publications in English language. Therefore, those scientific journals in different countries that publish innational languages have less chance to be evaluated based on bibliometric indicators. For this reason, Regional Information Center for Science andTechnology (RICeST) affiliated to the Ministry of Science, Research and Technology of Iran started to construct the Persian Science Citation Index(PSCI) and Persian Journal Citation Reports (PJCR) as products of ISC in 2000, and released the services from 2004. PJCR and PSCI are used toconduct the research. At the time of the study 51 Persian engineering journals were indexed in ISC with IF in PJCR. The aim of the study is tofind if the JIF is affected by both ASC and JSC for Persian journals in engineering subject category during 2002-2006. The results show that withinthe five years mean rates for JSC and ASC are 41% and 66%, respectively. Findings also report that the correlation between JSC and ASC with IF isstatistically significant (R= 0.300, sig. = 0.032; R= 0.397, sig. = 0.004, respectively). Moreover, after self-citation removal, the maximum rankingschange was observed (either positive or negative). With or without inclusion of author self-citations and journal self-citations about 13.7% and 15.7% ofjournals maintained the position. There is also no correlation between JIF and the number of articles (R= - 0.031, sig. = 0.831). According to thefindings, the study suggests that Persian journals' editorial boards in engineering field implement a policy with regard to articles selection as wellas authors' citation behavior.