To understand the role of tissue inhibitors of metalloproteinase-1 and -2 (TIMP-1 and TIMP-2) in intraocular diseases, levels of TIMP-1 and TIMP-2 were measured by enzyme immunoassay in 47 patients with various ocular diseases: in subretinal fluid of 7 patients with rhegmatogenous retinal detachment and in vitreous of 12 patients with proliferative diabetic retinopathy, 4 with proliferative vitreoretinopathy, 2 with vitreous hemorrhage due to branch retinal vein occlusion, 12 with idiopathic macular hole, 3 with retinal detachment due to high-myopic macular hole, 4 with macular epiretinal membrane, and 3 with choroidal neovascular membrane due to age-related macular degeneration. TIMP-1 levels were significantly higher in subretinal fluid than in vitreous fluid with any diseases (P < 0.0001, Mann-Whitney U test). TIMP-1 levels in vitreous fluid of the eyes with proliferative diabetic retinopathy and proliferative vitreoretinopathy were higher than those in vitreous with other diseases (P < 0.0001). In contrast, TIMP-2 levels were not elevated in the subretinal fluid and vitreous. TIMP-1, but not TIMP-2, was secreted into the subretinal space in rhegmatogenous retinal detachment, and also into the vitreous in eyes with proliferative disease, suggesting that TIMP-1 would play a specific role in the process of these diseases.