Infectious disease is a rare cause of parkinsonism. We report a 7-year-old boy who developed flu-like symptoms followed by parkinsonian features including hypophonia, hypomimia, bradykinesia, and dystonia. A T2-weighted brain magnetic resonance imaging showed high signal intensities in both basal ganglia. The results of serial serologic tests of Mycoplasma pneumonia antibody suggest that this movement disorder was associated with Mycoplasma pneumonia infection. The patient's symptoms gradually resolved, and the basal ganglionic lesions disappeared on follow-up magnetic resonance imaging.