It has been documented in nowadays the increase of bacterial resistance to antibiotics. So the current research aims to investigate the correlation of E. coli resistance with occurrence of virulence factors, and to achieve this goal the following has beenFirst: 28 calf isolates and 5 human isolates were identified biochemically by lactose fermentation, indole, citrate, methyl red, voges proskaur tests.Second: 14 isolates from calf samples and 5 isolates from human specimens were studied for antimicrobial susceptibility patterns by disk diffusion tests using 14 antimicrobial disks.Third: the most five resistant and the most five sensitive E. coli isolates were subjected to multiplex PCR with primers specific to the most common virulence genes (Stx1, Intimin, F41, K99, STa and Stx2).