One of the affective variables influencing education-instructional process is anxiety. In teaching of writing skill, anxiety is an important variable to be taken into consideration. The anxiety that hinders the development of individual writing skills stems from the convergence of various variables. In order for writing education to be effective and productive, anxiety must be taken into account. The purpose of the current study is to develop a reliable and valid writing anxiety scale for secondary school students. The study was conducted on 500 students attending secondary schools in the city of Istanbul. A total of 96 students randomly selected from these schools were asked to write a composition explaining their opinions about writing; thus, qualitative data were collected. On the basis of the students’ composition, a draft scale consisted of 46 items were developed. The piloting of the draft scale was performed on 48 secondary school students. On the basis of expert opinions and student feedbacks, the scale was reduced to 38 items. The scale obtained in this way was administered to 500 secondary school students. As a result of the analyses conducted, Kaiser-Meyer-Olkin (KMO) value of the scale was found to be .838; its Bartlett’s Sphericity Test value was found to be (χ2=1767,902; sd=171 p<. .000). Cronbach’s Alpha reliability coefficient used to calculate the internal consistency of the scale was found to be .790. As a result of the factor analysis, a total of 16 items subsumed under three factors and explaining 41.036% of the scale were obtained. In light of the findings of the study, it can be argued that the scale is valid and reliable. The scale can be used to measure secondary school students’ writing anxiety.