Synovial sarcoma is a rare soft tissue tumor accounting for 5-10% of soft tissue sarcomas. Most arise in the extremities and trunk, and a small proportion occur in the abdominal wall, head and neck legion, and mediastinum. It manifests different phenotypic subtypes that render their cytologic evaluation challenging. Moreover, cytomorphologic description of the epithelial component of synovial sarcoma is rare in Korea. We report a case of biphasic synovial sarcoma on the right lower extremity in a 49-year-old woman diagnosed by fine needle aspiration cytology. The aspirate was moderately cellular and composed of a mixture of tissue fragments and dissociated cells with bland chromatin, inconspicuous nucleoli, and oval to spindle-shaped cytoplasm. Mitosis was rare. A monolayer sheet of epithelial component was seen. The cells in this monolayer sheet had more abundant distinct cytoplasm, round nuclei, and prominent micronucleoli. Histologic examination showed a biphasic pattern consisting of mostly sarcomatous stroma and a few small glandular areas at the periphery of the tumor.