While research mainly focuses on identification of anxiety, its causes and effects on the learning process and the ways to allay anxiety among foreign language learners, foreign language teaching anxiety has remained a research area that has not attracted much attention. Therefore, in the context of teaching anxiety among pre-service teachers of English as a foreign language (EFL), the current study aims to investigate the sources of foreign language teaching anxiety (FLTA). The sample group in the study consisted of 60 pre-service teachers. A background questionnaire, interviews, reflections and essay papers were used to collect qualitative data. The results indicated that pre-service teachers experience FLTA before, during and after their teaching activities. The study also concluded that the sources of FLTA are teachers' personality, perceptions of low level language proficiency, fear of negative evaluation, teaching demotivation and amotivation, teaching inexperience and technical concerns. It was recommended that the curricula of pre-and in-service training programs should include topics to raise awareness of FLTA.