Objective To observe the feasibiliy, safety and efficacy of 125I seed implantation for the treatment of ocular tumor. Methods Nineteen patients received 125I seed implantation through intra-operative direct vision. In which 3 patients who had tumor spread received secondary 125I seed implantation through CT or MRI guiding. Nineteen patients received the operation successfully according to the preoperative plan. Fourteen cases were implanted 125I seed once, three cases received twice implantation, one case received implantation for three times, and one case received implantation for four times. Results The 19 cases were observed for 2 weeks to 8 years, The average follow-up time was (26.55±5.46) months. Local lesion was controlled without recurrence in 14 cases(73. 68%). New lesions occurance or the primary lesions spreading was found in 5 cases (26. 32%), and they were controlled after secondary 125I seeds implanation. No metastasis occurred. There was no complication associated with the manipulation of implantation surgery, except for 3 cases of mild eyelid swelling and subsutaneous hemorrhage. Conjunctival hyperemia and epithelializeation, tearing, increase of secretion were observed when the 125I seed implanted anterior to the equator, and eyelashes (eyebrow) loss occurred within 1 to 3 months. Those symptoms disappeared 6 months later. One case suffered skin ulceration and fistula because of the implantation site of the seed was close to the skin. In the patients that 125I seed implanted in lacrimal gland area, one case developed dry eye, and it was recovered in 6 months. In the patients that 125I seed implanted in the middle and the posterior part of orbit, fibrosis, sclerosis and skin pigmentation occurred 9 months after surgery. All the complications were recoverable. The anterior part complations were disppear 6 months after the surgery. Conclusion Implantation of 125I seed for the treatment of ocular tumor can utmostly reserve the visual function and the appearance, which has exact effect and safety with less damage and less complication. Key words: Tumors, ocular; 125I seed, implantation; Efficacy; Complication