A 31-year-old woman developed dissociated sensory loss below the right C-3 dermatome within an hour after acupuncture therapy for the left posterior neck pain. Moxa has been applied on the top of the acupuncture needle: Moxa needle. T2-weighted MR images on the following day showed a high-signal cord lesion at the C1/2 level on the left. After 10 days, the MRI lesion became clear; it involved the left lateral spinothalamic tract and the lateral corticospinal tract; however, her muscle strength and deep tendon reflexes were normal. The C1/2 focus reduced slightly 2 months after the accident, and the sensory impairment was localized below the Th7 dermatome. It was suggested that the cervical cord lesion was caused by the direct insertion of and thermal injury by the Moxa needle.