The authors report 32 cases of histologically proven ocular reticulum cell sarcoma (RCS). Follow-up data are available for all patients. Twenty-six patients (81%) have died and the mean survival time was 20 months from the time of diagnosis of RCS. Diagnosis of ocular involvement was made by vitreous biopsy in 56% of cases, enucleation in 13%, and postmortem examination in 31%. The mean age at the time of diagnosis was 60 years. Central nervous system (CNS) involvement was present in 56% of patients, visceral involvement in 16%, and both CNS and visceral involvement in 6%. Isolated ocular disease occurred in 22% of patients. Results of head computed tomography (CT) and cerebrospinal fluid examination more often disclosed evidence of RCS than did body CT or nuclear medicine scans. Responses to treatment were variable, but prognosis for survival is poor.