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Verotoxigenic Escherichia coli (VTEC) are major foodborne pathogens with an increasing public health concern. The purpose of this study was to investigate the occurrence and the phylogenetic groups of VTEC isolates from the feces of healthy sheep and broiler chickens at a slaughterhouse in Urmia region, Northwestern Iran. A total of 446 E. coli isolates (97 from sheep and 349 from broiler chickens) were assessed for the occurrence of the Vtx-encoding genes (vtx1 and vtx2) using polymerase chain reaction. Then, all the recovered VTEC isolates were phylogenetically grouped based on the Clermont phylotyping method using three genetic sequences, the so-called chuA, yjaA, and TSPE4.C2. The vtx gene-carrying E. coli was identified in 46.4% (45/97) of sheep-originated isolates and in 8.3% (29/349) of broiler chicken-originated isolates. In general, phylotyping revealed that 74 VTEC isolates segregated in the phylogenetic groups A (32.4%; designated as VTEC-A), B1 (44.6%; VTEC-B1), B2 (9.5%; VTEC-B2), and D (13.5%; VTEC-D). The results also showed that the dissemination of VTEC isolates of sheep and broiler chicken origin varied noticeably in their assignment to B1 and D phylogenetic groups (p<0.01). In addition, the virulent phylogenetic groups (B2 and D) were significantly more common in broiler chickens than in sheep (p<0.01). In conclusion, healthy sheep and broiler chickens could be a reservoir for VTEC belonging to virulent phylogenetic groups, thus representing a potential risk factor for public health. This study also demonstrated significant differences with respect to the phylogenetic group assignment of the VTEC strains between sheep and broiler chickens.