The purpose of this study was to compare the double disk synergy and E-test methods for detection of ESBL production in Enterobacteriaceae members. Totally 101 Enterobacteriaceae isolates including 71 Escherichia coli, 14 Klebsiella pneumoniae, 15 Klebsiella spp., and one Klebsiella oxytoca were included in the study. By double disk synergy method 86% of isolates were GSBL positive (87 isolates) and 81% (82 isolates) were positive by E-test method. The results were statistically evaluated and no significant difference was found between E-test and double disk synergy method.