This study investigated the predictive effect of in-service and pre-service science teachers' perceptions of the learning environment on their self-efficacy beliefs on science teaching. The same self-report questionnaires were used to collect data from in-service and pre-service science teachers. Of the participants, 142 in-service science teachers and 281 pre-service science teachers completed the Constructivist Learning Environment Scale and the Teachers' Sense of Efficacy Scale. Canonical analysis was used to investigate the relationships between variables. The analyses of the findings revealed a reciprocal relationship between variables. Both in- and pre-service science teachers' classroom environment perceptions were significantly related to their self-efficacy beliefs. Additionally, in-service science teachers scored significantly higher than pre-service ones for all variables and in-service science teachers' classroom environment perceptions were more strongly correlated with their self-efficacy beliefs than pre-service science teachers'. This study suggests that creating a more effective learning environment affects science teachers' sense of efficacy or science teachers with high efficacy beliefs create more constructivist classroom environment.