Avian colibacillosis can affect birds of all ages. It is now one of the major causes of economic losses in the poultry industry, as well as a public health risk all over the world.This study aimed to determine the occurrence of E. coli in market-age poultry and the risk of its zoonotic infections in Ismailia city, Egypt. A total of 350 samples were collected from the intestinal contents of the slaughtered poultry (100 farm chickens, 100 backyard chickens, 50 ducks, 50 geese, and 50 turkeys) in Ismailia City. On the other hand, a total of 200 samples were collected from humans at outpatient clinics (100 stool samples and 100 urine samples) from the same investigated area. Samples were examined using bacteriological and molecular examination for genus-specific and virulence gene detection. Results revealed that the isolation rates of E. coli were 70% in farm chickens and turkeys, 88% in backyard chickens, 86% in domestic ducks, 72% in geese. Of avian E. coli isolates, the rates of Shiga toxin-producing E. coli (STEC) strains were 91.4%, 96.6%, 90.9%, 41.7%, and 51.4%% in farm chickens, backyard chickens, ducks, geese, and turkey respectively. In humans, the isolation rate of E. coli was 42% in urine samples and 66% in stool samples. The human STEC isolates were higher in stool samples (26%) than in urine samples (6%). The isolation rates of E. coli were significantly higher in persons who were in contact with poultry than in persons who were not in contact with poultry (p ≤ 0.01). In conclusion, the high isolation rates of STEC and detection with similarities of some E. coli virulence genes (It, St, eaeA, Stx1, and Stx2 genes) from poultry intestinal contents and human samples indicated a significant risk of zoonotic transmission of E. coli via food chain in the investigated area.