High quality teaching, student learning, and students achievement is dependent on the skills teachers use and the existence of professional expertise such as teachers reflectivity. The purpose of this study was to see whether there was any relationship between Iranian EFL teachers reflectivity and their students' language achievement and whether there was any difference between teachers reflectivity, considering their teaching experience and level of education. For the study, 83 EFL teachers from nine language institutes in Isfahan, Iran, were randomly selected. Larrivee's (2008) reflectivity questionnaire, which classifies reflectivity into four levels: pre-reflection, surface reflection, pedagogical reflection, and critical reflection, was used for data collection; furthermore, an observation checklist, based on the questionnaire, was also used. Data analysis revealed that the more experienced the teachers, the more reflective they were; moreover, teachers with higher degrees were more reflective. In addition, there was a positive relationship between teachers reflectivity and students achievement.