Introduction/Context Listeria monocytogenes (Lm) is a bacterium that causes a food-borne illness, the Listeriosis. The rapid screening of the strains is crucial to conduct investigation, differentiate strains, understand the entry and the transfer of Lm in the production sites. A new method based on twelve multiplex real time PCR was developed in 2021 by the European Union Reference Laboratory (EURL) for Lm. It is an alternative for the characterization of 30 Lm multi locus sequence typing (MLST) clonal complex (CC) obtained conventionally by whole genome sequencing (WGS). The CCs are an universal language for strain typing and provide information on strain virulence. Objective The aim of this study was to assess the diversity of CC found in several dairy production sites, to determine CC for each tested strain and to compare them with a CC deduction from PFGE fingerprints. Materials and Methods A total of 47 strains from 3 dairy production sites were typed both using the multiplex real time PCR method and a PFGE (Pulsed-field gel electrophoresis) approach using ApaI and AscI enzymes. Results and Discussion A total of 20 CCs were identified among the 47 strains analysed using the multiplex real time PCR method and 18 via the PFGE approach. Of these CCs, 12 were perfectly concordant between the two methods, four being identified only by the PCR method and two only by the PFGE method. Only one inconsistency was identified during the study, the PCR result being the one to be considered. Conclusion/perspectives The multiplex real time PCR method represents a complementary approach and a key tool for assisting food laboratories to establish strain relatedness and for helping food business operators by improving their microbiological management plans.