An 8-year-old girl was admitted with vision loss. She had no history of amblyopia or other eye diseases. On examination, both eyes showed vision loss and uncorrected myopia, regardless of visual acuity correction by glasses. Her symptoms were considered exacerbated by fatigue. We diagnosed tonic accommodation because a regulatory paralysis agent provided relief. The patient had been treated with tropicamide methyl sulfate and neostigmine, but her visual acuity did not change. Based on a Kampo diagnosis, she was prescribed Shokenchuto. After 4 months' administration, her uncorrected vision improved by 1.2 in both eyes, and her visual acuity was maintained even when fatigued. Kampo medicine can be a treatment option for tonic accommodation in cases where standard treatments are ineffective.