The aim of this study was to investigate if extended-spectrum β-lactamase producing Escherichia coli (ESBL-EC) is present in intestinal tracts of apparently healthy broiler chickens at large-scale chicken farm and pigs, and their environments in Vietnam. ESBL-EC was isolated from 86.7% cloacal swabs of chickens (13 out of 15), 55.0% ectal swabs of pigs (11 out of 20) and 100% from their surroundings (2 beddings in a chicken farm and 2 drainages in pig farms). All the isolates from chicken and pig farms were multidrug-resistant. Interestingly, 94.7% (36/38) solates from chicken were resistant to ciprofloxacin and mcr-1 gene-positive (related to colistin resistance), respectively, while ciprofloxacin resistance and mcr-1 gene was found in only 12.8% (5/39) and none (0/39) from pig, respectively. CTX-M type in most of the chicken isolates belonged to group-1 whereas that in the pig isolates belonged to group-9. Virulence gene profiling revealed that some of these isolates indeed carry eae or astA pathogenic genes. Plasmid profiling and PFGE analysis indicated that most of them showed various genotypes although some isolates showed nearly identical genotype, suggesting that a number of ESBL-EC with various genotypes were distributed in chickens and pigs in Mekong Delta. To the best of our knowledge, this is the first report regarding isolation of ESBL-EC from broiler chickens in large scale-farms and pigs in Vietnam. Taken together, these results suggest that chickens and pigs in Mekong Delta, Vietnam used for food industry could also serve as reservoirs of ESBL-EC isolates carrying virulence genes.