Objective To evaluate the effect of transpupillary thermo therapy (TTT) on the treatment of intraocular tumors. Methods A total of 50 patients with intraocular tumors, including 37 choroidal hemangioma, 2 retinal capillary hemangioma, 5 choroidal osteoma, 4 choroidal melanoma, and 2 retinoblastoma (RB) underwent TTT and were followed up for 1~20 months. Results In 30 patients with choroidal hemangioma (average follow-up was 5.1 months), 29 (96.7%) had pigment scarring in different levels and the retinal detachemnts were partly or completely recovered; 1 had no obvious improvement. The visual acuity was unchanged in 24 (80.0%) patients, improved in 41 (13.3%) and declined in 2 (6.7%). In 2 patients with retinal capillary hemangioma, no effect was found. In 5 eyes (4 patients) with choroidal osteoma (average follow-up was 6 months), no change of the tumor was found in 1 and the atrophic spots were seen in 4; the visual acuity was unchanged in 3, improved in 1 and declined in 1. In 4 patients with choroidal melanoma (average follow-up was 8 months), the tumor was shrunken in 1, unchanged in 2, and enlarged in 1; the visual acuity was unchanged in 2 and declined in 2. In 2 patients with RB, RB was totally shrunken in 1 and partly shrunken in 1. Visual acuity of one child patient who was followed up for 20 months could not be examined, and was unchanged in another one who was followed up for 3 months. No severe complications were found in the patients during the treatment and the follow-up. Conclusions TTT is effective for the treatment of some intraocular tumors except retinal capillary hemangioma. It is a kind of potential treatment for intraocular tumors with few side-effect. (Chin J Ocul Fundus Dis,2003,19:144-148)