The present study investigates awareness, factual knowledge, opinions, and risk perceptions of students from Turkish middle schools with regard to nanotechnology in a very general sense. The study was carried out among 1,396 middle school 6th, 7th, and 8th grade students. The students' perceptions of and opinions about nanotechnology were elicited through a questionnaire developed by the authors. Students have some awareness of nanotechnology and most students had positive emotions and opinions about it. Students' risk perceptions of nanotechnology and the influence of the demographic and affective domain, achievement in science courses, and science motivation on these perceptions were also investigated. The results show that, for gender, no significant difference was observed. However, for some of the demographic and affective domain factors, and achievement in science courses, significant differences were found.