Organophosphate intoxication causing the extrapyramidal symptom is not frequent. A case of Parkinson's syndrome caused by organophosphate intoxication was observed, of which is reported with the quantitative measurement of tremor using Tri-axial accelerometry. A fifty nine year-old male was admitted to Wonju Christian Hospital after the intake of organophosphate for the purpose of suicide and three days after the accident, involuntary movements were detected. The encephalography and MRI showed no abnormality. With Tri-axial accelerometry, we detected less than 4 Hz resting tremor. The tremor did not response to L-dopa, and in the follow up examination performed 149 days after the accident, an increase in amplitude was detected. Gait disturbance and dysarticulation became more severe. In a case of the organophosphate intoxication patient, very rare Parkinson's syndrome findings were detected, and the tremor during the resting period was measured quantitatively by electromyography and Tri-axial accelerometry. (J Korean Acad Rehab Med 2010; 34: 110-113)
