Abstract This study aimed to assess the impact of critical reflective thinking (CRT)-based workshops in developing EFL teachers' teaching and language testing skills. Subsidiary aims of the study include: ascertaining EFL teachers' perceptions of their own teaching and language testing skills both before and after CRT-based workshops. The study made use of both the interpretive constructivist mode of inquiry and the quasi-experimental research design. Data were collected using three instruments: (1) Teacher Self-Appraisal Form; (2) Language Tests Checklist; and (3) Semi-structured Focus-group Interviews. Participants were 12 EFL university teachers working in the English department at College of Arts, King Khalid University, Saudi Arabia. They belonged to a variety of academic, social and cultural backgrounds. The CRT-based workshops addressed three components: cooperative learning, thinking maps and language testing. Analysis of data indicated a positive impact of the CRT-based workshops on developing trainee teachers' perceptions of their own teaching and language testing skills. Findings also indicated a positive impact of the CRT-based workshops on developing trainee teachers' language testing and language test-items development skills. Findings of the study were discussed and a set of implications and recommendations were highlighted.  -----------------------------------------------