Laser photocoagulation might aggravate the ischemia of an area of retinal detachment and predispose the retina to formation of neovascularization and an angioma-like lesion. We present a case of retinal neovascularization (RNV) and an angioma-like lesion occurring after demarcation photocoagulation for rhegmatogenous retinal detachment (RRD). A 20-year-old woman suffered from a retinal atrophic hole with localized shallow retinal detachment in the right eye. Laser photocoagulation was performed to wall off the area of detachment. Fifteen months later, RNV and an angioma-like lesion had developed in the previously detached retina. Treatment with demarcation photocoagulation for RRD may run a risk of formation of RNV and angioma-like lesion if the retina is not reattached.