Aims: Teachers' stress and anxiety affects their occupational function and leads to weak function, absence from work, exhaustion and depression. The purpose of this study was to investigate the effects of teachers' anxiety on the quality of teaching in the classroom.

  Methods: This descriptive comparative study was performed in 2010-11 on all male and female high school teachers of Sabzevar. The sample of this study included 30 high school teachers both men and women and 300 of their students. Sampling was done using the simple random method. At the first step the teachers filled out the Cattell's anxiety questionnaire, and were divided into two groups (15 anxious and 15 non-anxious) with regard to their total scores. Then the Siraj's questionnaire of teaching quality (2003) was filled out by 300 of their students. Data were analyzed by descriptive statistics and Kolmogorov-Smirnov and independent t-test using SPSS 16 software.

  Results: There was a significant difference between the total score of the teaching quality of anxious and non-anxious teachers (t=2.95, df=268, p=0.003), so that the teaching quality of non-anxious teachers was higher than anxious teachers.

  Conclusion: Teacher's anxiety affects the teaching quality to a high extent. There is significant difference between anxious and non-anxious teachers in the indicators of "teaching performance" and "interpersonal relations", but there is no significant difference in the indicators of "lesson plan" and "evaluation" between anxious and non-anxious teachers.