Four patients are reported with massive edema of the ovary which was mistaken grossly for neoplasm at celiotomy. The ovaries were large, white, and wet. Microscopically, they resembled soft fibromas and consisted of hyperplastic cortical tissue separated by proteinaceous fluid. In one instance, there was an associated luteincell hyperplasia; this patient had evidence of masculinization. The other 3 patients presented with abdominal pain. The most probable pathogenesis is partial torsion, possibly recurrent, of the mesovarium. Consideration should be given to the preservation of such ovaries by securing them in a position from which they cannot twist.