Background: The aim of this study was to investigate the antimicrobial activity of Mentha piperita , Withania somnifera and Rosmarinus officinalis extract on antibiotic resistant Escherichia coli isolated from poultry stool in Zabol city. Materials & Methods: The extract of Mentha piperita, Rosmarinus officinalis and Withania somnifera was prepared by rotary machine. Escherichia coli strains were isolated from poultry stool samples. Minimum inhibitory concentration and minimum bactericidal concentration were determined by microdilution method. Results: The results of this study showed that Mentha piperita extract showed the highest inhibitory ratio compared to other extracts. The minimum inhibitory concentration was 3.1 ppm, with 5 strains inhibited at this concentration. Discussion: The results of this study could be an effective strategy for production and preparation of medicinal plants to help treating E. coli infections.