The purpose of this project is to study the nanotechnology researchers’ information needs and information retrieval behavior. Its Methodology is questionnaire survey. Research instrument was a researcher-made questionnaire whose reliability was calculated through Cronbach α (α= 0,914) and whose content validity was analyzed and approved through expert opinions.1225 researchers in nanotechnology are included as the research population out of whom 291 researchers, based on Krejcie and Morgan table, were selected using cluster random sampling method. Out of distributed questionnaires (500), 243 of them (84% of the sample) were returned completed. Statistical analyses were carried out in SPSS and Excel environments. The results of research indicate that, 69.7 % researchers mainly use articles, 58.8 % of them e-journals, and a few of them use bibliographies as formal sources. Their ideal type of resource is e-resources. Their motives to use information are mainly conducting research projects and updating their field-related information. Academic centers are where they usually refer to address their information needs. The major problems to access information are inappropriate internet services and lack of access to certain data bases due to subscription issues.