Learners' motivation has been widely accepted as a key factor which influences the rate, success, and failure of second/foreign language learning. On the other hand, demotivation is regarded as a flip side of motivation which has negative effects on language learning processes and outcomes. This study intended to examine what factors may demotivate Persian language learners in a classroom. It also investigated the frequency and order of significance of the demotivating factors to find out which factors are the most influential and also explore their relations to gender and level of education of the learners. In order to achieve the objectives of this study, approximately a hundred learners were asked to complete a questionnaire, which included background questions concerning sex, age, level of the study, and the nationalities of the participants on the basis of which five demotivating factors were identified. The findings indicated that while there were no significant differences between male and female participants in terms of some demotivating factors, significant differences were observed between learners at different levels of education with regard to some other demotivating factors. Implications for non-Iranian Persian language learners are discussed.