In order to define the role, the risk factors, and the clinical and laboratory characteristics of Mycoplasma pneumoniae infection in children with pharyngitis, 184 patients with acute non-streptococcal pharyngitis (102 males; median age, 5.33 years) were studied. Acute Mycoplasma pneumoniae infection was demonstrated in 44 (23.9%) patients. A history of recurrent episodes of pharyngitis (defined as at least 3 acute episodes of pharyngitis in the 6 months preceding enrollment) appeared to be the more useful parameter for differentiating Mycoplasma pneumoniae pharyngitis from non-streptococcal non- Mycoplasma pneumoniae pharyngitis ( P<0.05 in multivariate analysis). These data, which highlight the emerging role of Mycoplasma pneumoniae in acute pharyngitis, must be taken into account in the diagnosis and treatment of this clinical manifestation in children.