Six solid intraocular tumors were reliably diagnosed by needle biopsies and cytologic examination of the aspirates. All of the tumors had an unusual clinical or diagnostic feature that raised the possibility of a non-melanomatous tumor. Two intraocular lesions that were obscured by opaque media or a retinal detachment were successfully biopsied under B-scan ultrasonographic guidance of the needle. Cytodiagnosis of narrow spindle B, plump spindle B, and eipthelioid cell types, as well as one case of Coats' disease, was possible and correlated closely with the predominant cell types comprising the lesions discovered on histopathologic examination of the globes that were enucleated. The ocular tissues were not significantly disturbed and hemorrhage was not a serious problem. Details of the biopsy and cytologic techniques, the major clinical indications, for the procedure, and the authors' belief that the procedure is not likely to produce local seeding or extraocular metastasis in cases of melanoma are presented and discussed. Considerable profit may attend the use of this technique for the diagnosis of possible metastatic lesions and tumors of the ciliary body. The technique, however, should not be routinely employed and should be restricted to extremely difficult diagnostic problems.