Inflammatory pseudotumors rarely occur in the spleen. We report such a case with characteristic computed tomography (CT) and magnetic resonance imaging (MRI) findings. A CT scan showed an isodense nodular mass with gradual mild enhancement on delayed-phase contrast-enhanced images. MRI showed a mass with isointense signal on T1-weighted images and hypointense signal on T2-weighted images. The tumor mass showed progressive inhomogeneous enhancement on gadolinium-enhanced images. The patient received splenectomy, and histologic diagnosis was compatible with inflammatory pseudotumor.