Described in this paper are the ultrastructural features of three cases of palisaded intranodal myofibroblastoma. The tumor cells were identified as myofibroblasts. Abortive vessels formed by the tumor in one case and spindle cell tumorous proliferation outside the tumor capsule and centered on the veins were composed of the same cell types as the cells of the main tumor mass, suggesting that the tumorous myofibroblasts might have originated from the modified smooth muscle cells. The various stages of formation of the intracytoplasmic fuchsinophilic bodies are described in our report.