This study aims to investigate teachingself-efficacy level of science teachers in relation to some variables. Thestudy, in which quantitative research method and relational survey model wereused, was conducted with the participation of 501 science teachers in the statemiddle-schools of Istanbul province selected by using random sampling methodthroughout the academic year of 2015-2016. In the study, Teacher Self-EfficacyScale was used as an instrument for collecting data. At the end of the study it has been foundthat there is a substantive correlation between self-efficacy level of scienceteachers and the variables of “seniority” and “graduation status”(undergraduate, postgraduate etc.). Moreover, a statistically significantdifference has been found between classroom-management factor which is placedas the second one on the Teacher Self-Efficacy Scale and the variable of“having a teacher in the family”. No statistically significant difference hasbeen noted between teacher self-efficacy level and the variables of “gender”and “type of the schools where teachers graduated from (undergraduate, collegeetc.)”.