Bacteria of the Arcobacter genus are associated with intestinal diseases, both in people and in animals, it has also been included in the group that causes foodborne diseases, since it is frequently found in the food chain. For this reason, in our research, the objective was to characterize Arcobacter spp isolates molecularly from milk serum samples from the cheese factories of the Salinas parish, Guaranda, Ecuador, for which the pathogen was isolated from serum samples. milk in media and specific culture conditions in a plate, the microorganism was characterized by Gram staining and biochemical tests, after which the DNA was extracted and amplified by Polymerase Chain Reaction, finally, the antimicrobial activity against to two flouroquinolones. After the analysis, of the 50 samples of milk serum, 28 samples presented translucent colonies and the majority were Gram (-), after carrying out the biochemical tests, the behavior of the microorganism coincides with the pathogen of interest, finally, after the amplification was carried out. of the genetic material by PCR, it was confirmed that 26 of the 28 (52%) isolated strains belonged to the Arcobacter genus, in antimicrobial activity, the microorganism was susceptible to the control antibiotic levofloxacin, while some samples presented resistance to ciprofloxacin. In conclusion, since the microorganism is present in dairy serum, cheeses could act as a vehicle for transmission to humans and represent a potential risk to public health.