Objectives The last two years, clinical cases of tinea capitis caused by Microsporum audouinii (M. audouinii), have increased in Belgium. To better understand the emergence of this species in the population, the Belgian National Reference Center (NRC) for dermatophytes launched a national survey in 2013. Epidemiological aspects and genotypic characterization of the strains were included. Methods The study was conducted from March 2013 up to February 2014. All Belgian laboratories were asked to send M. audouinii strains isolated from hair to the NRC with a form to fill in including epidemiological informations. The fungal strains were identified by microscopy or ITS sequencing in case of doubt. The genotypic analysis was performed by the DiversiLab® system (bioMérieux) for DNA fingerprinting and analysis. Epidemiological informations were analyzed with the help of a biostatistician. Results Among the collected isolates, 117 strains have been currently confirmed as M. audouinii. Analysis of the epidemiological characteristics of the infected population shows that the main age category concerns 5-9 year-old children (64%, p< 0,0001) with a sex-ratio M/F of 1.97. Data concerning the geographic origin of the family have been obtained in only 33,6% of the cases. It reveals that strains have been mainly isolated from patients with a Belgian nationality (43,6%) suggesting bias in the data collection. The geographic origin of the remaining group includes several African countries such as Congo (20,61%), Guinea (12,8%) and Burundi (5,12%). The genotypic analysis led to the distinction of 6 genotypic variants of M. audouinii. One of these variants was exclusively recovered from South Belgium (11 strains). The major group was composed of 96 strains, well distributed in different Belgium locations. Two other groups of three strains each were close to the major group but the analysis of the spectral superposition showed some differences between these groups. The two last groups were clearly different from the major group ...