the aim of the present study was to investigate the effect of reflection-based workshops on developing the in-service EFL teachers' teaching writing processes. Subsidiary aims of the study include: ascertaining the EFL secondary teachers' perceptions of their writing processes. The study made use of both the interpretive constructivist mode of inquiry and the quasi-experimental research design.  The instruments of the study were a writing processes checklist, an in-service EFL teachers' perceptions of teaching writing processes questionnaire and their reaction on reflection-based workshops questionnaire . The sample of the study included 12 in-service EFL teachers at Al–Salhyia Directorate, Sharqyia Governorate. The reflection-based workshops addressed five main processes namely: prewriting, planning, drafting, editing and publishing Analysis of data indicated a positive impact of the reflection based workshops in developing in-service EFL teachers' perceptions of teaching writing processes and improved their reaction towards them. Findings of the study revealed a positive effect of the  reflection-based workshops on developing in-service EFL teachers' teaching writing processes.