We studied the association between herpes simplex virus-1 (HSV-1) infection and Bell palsy in children. Thirty-three of 42 affected patients had a positive HSV-1 enzyme-linked immunosorbent assay compared with 16 of 41 controls (P = 0.0003). Ten of 47 affected patients had a positive HSV-1 polymerase chain reaction compared with 4 of 45 of controls (P = 0.08). Our findings support an association between HSV-1 infection and Bell palsy in children.