A 56-year-old female presented with transorbital penetrating injury caused by bamboo fragments, which resulted in brain abscess 2 weeks after the injury. Initial computed tomography (CT) of the head did not reveal the foreign bodies. However, follow-up CT demonstrated a well-defined hyperdense abnormality of 1.0 cm length in the left orbit and brain abscess in the left temporal lobe. The lesion corresponding to the hyperdense abnormality on CT appeared isointense on T₁-weighted magnetic resonance (MR) imaging and hypointense on T₂-weighted MR imaging. The bamboo fragments were surgically removed, and aspiration and continuous drainage were performed for the brain abscess. The postoperative course was uneventful and the patient was transferred to a local hospital with minor neurological deficits. Bamboo foreign bodies may show changes in properties on CT and MR imaging in the subacute stage. Careful radiological examination and follow-up monitoring are required for the correct diagnosis and treatment of such injuries.