Trichophyton tonsurans is a highly transmissible anthropophilic dermatophyte fungus, which invades keratinized tissues. This study reports a case of family microepidemic caused by this dermatophyte. Despite their excellent hygiene conditions, it remained active for several years, spreading to all family members. The hypothesis that the fungus was being kept alive in the family home was confirmed after samples collected from it were analyzed. Pure cultures of the fungus were isolated and identified. After diagnosis, the house was disinfected with concomitant oral treatment for all family members.