The authors observed for 5 to 18 years 41 patients (22 women and 19 men) with malignant iris melanoma and/or malignant melanoma of ciliary body. The age of the patients was 20 to 80 years. All patients underwent surgical treatment with preservation of the eye ball. In 21 cases iridectomy, in 18 cases iridocyclectomy, and in the remaining cases iridocyclectomy-choroidectomy was performed. In 25 eyes the tumour occupied less than 1/4, and in 16 eyes between 1/4 and 1/2 of the iris circumference. During the period of observation 7 eye balls were enucleated, and in 6 recidivation of the tumour was diagnosed. These patients belonged to the group of 18 people with the tumour occupying the iris and the ciliary body, or the ciliary body only. Mortality in this group was 28%. Among 5 patients who died, in 3 the tumour occupied more than 1/4 of the iris circumference. In 3 patients from this group recidivation was diagnosed, in 4 enucleation was necessary. In 4 eyes secondary glaucoma was diagnosed. Therefore, among risk factors one ought to list size of the tumour, recidivation, and secondary glaucoma. On the other hand infiltration of the sclera and of the optic nerve was found only in one deceased person. The authors have not been able to obtain current information about 2 patients. In the whole studied group mortality was 5 out of 39, that is 12.8%. The most common complication during the surgery was hemorrhages. Two other complications: complicated cataract, usually stationary, and secondary glaucoma occurred both before and after treatment. Despite of complications 68.3% of patients maintained good visual acuity.