Nasal polyposis is characterized by benign, non-cancerous and painless growths originating in the tissue of the nasal cavities and paranasal sinuses. Polyps arise from chronic inflammation due to asthma, recurrent infections, allergies, drug sensitivity or immune disorders. They can obstruct the nasal cavities and thus cause respiratory problems, a reduction in the sense of smell and susceptibility to infections. Furthermore, nasal polyps can recur. Hence the importance of using valid diagnostic methods. In this work, the diagnostic investigation carried out by scanning electron microscopy (SEM) and nasal cytology led, for the first time, to the identification of a mycoplasma superinfection on nasal polyposis.