A total of 188 joint samples has been collected from commercial meat chicken with lameness from poultry farms in the middle (Hama) and coastal regions (Tartos) of Syria. These joint samples were taken from cases of arthritis and included hip, knee, hock, foot pad .Surfaces of joints were disinfected. Joint samples were cultured on (MacConkey agar - EMB agar) and identified on the basis of biochemical tests, by using HiMotility biochemical kit for E.coli. So, we obtained in total (72.9 %) isolates from infected joint samples. (74.1%) isolates from Hamaand (70.8 %) isolates from Tartos. The rates of isolation of E. coli were (20.4%) from knee joints, (14.6%) from hip joints and (13.9%) from foot joints, but the higher rate was from hock joints (88.3%). The motility of all isolates as one of the virulence factors were tested and found that (95.3%) from Hama and (95.1 %) from Tartos isolates were motile. The hemolysis, as another virulence factor, was tested in all isolates and we found that (95.7 %) of Hama and (94.6 %) of Tartos isolates were hemolytic. Isolates were serotyped by agglutination test with specific antisera of somatic antigen to five serogroups O1, O6, O8, O15 and O78 which are considered to be one of the most prevalent and pathogenic serogroups in poultry farms. The higher percentage was O1 (35.3 %) and (31.4%) from the isolates of Tartos and Hama, respectively