Escherichia coli is the most common pathogen isolated from nosocomial and community acquired urinary tract infections. It is relatively difficult to treat infections caused by extended-spectrum beta-lactamase-(ESBL) producing E. coli strains. Nitrofurantoin is used for non-complicated urinary tract infections. The aim of this study was to determine the in vitro activity of nitrofurantoin against E. coli strains isolated from urine in the Bacteriology Laboratory, Ege University Hospital, January-December 2006. Identification of E. coli strains and activity of nitrofurantoin were studied using the automated VITEK 2 system. Identification of ESBL (+) E. coli and susceptibility to nitrofurantoin were determined and interpreted according to the CLSI criteria. Of 594 E. coli isolates, 70 (11.8%) were resistant to nitrofurantoin. Resistance to nitrofuratoin was higher in ESBL (+) strains (27/409 vs 43/185, Chi-square, p<0.05). Nitrofurantoin showed very favorable in vitro activity against ESBL producing E. coli. Further clinical evaluation is needed to decide whether this agent can be a good alternative to the presently used agents in urinary infections.