This study aimed to determine the characteristics of antibiotic resistance in strains of Escherichia coli isolated from lettuce. 3 vegetable crop production sites were randomly selected. A total of 60 lettuce samples were taken from 20 lettuce plants randomly collected per site. Escherichia coli strains were isolated on Rapid E.coli 2 medium and their identification confirmed on API 20E gallery. Then, an antibiotic susceptibility test using the disk diffusion method in Müller-Hinton agar medium was carried out on the identified strains. The results revealed relatively high resistance rates to amoxicillin (73.5%, 66.5% and 62.5% at sites 1, 2 and 3 respectively) and tetracycline (86% for site 1, 67% for site 2 and 79.5% for site 3). The proportions of expanded-spectrum betalactamase were 22.5% for site 1, 44.5% for site 2, and 56% for site 3. A total of 246 extended-spectrum betalactamase-producing strains were observed out of 600 strains isolated, i.e. 41%. The resistance genes BlaCTXM, BlaSHV and BlaTEM were observed in the respective proportions of 32.5%, 43.1% and 56.1% in extended-spectrum betalactamase-producing strains. These antibiotic-resistant strains of Escherichia coli could constitute a health hazard for humans, because lettuces are vegetables eaten raw.