Objective To observe the efficacy of transscleral subretinal fluid drainage and cryotherapy combined with intravitreal injection of conbercept, an anti-vascular endothelial growth factor (VEGF) drug, in the treatment of stage 3 Coats disease. Methods The clinical data of 1l patients (11 eyes) with stage 3 Coats disease were analyzed retrospectively. The patients were aged 2-16 years old, with 10 boys and 1 girl; 7 eyes with partial retinal detachment (stage 3A) and 4 eyes with complete retinal detachment (stage 3B). All eyes were treated with transscleral subretinal fluid drainage and retinal cryotherapy combined with intravitreal injection of conbercept (an anti-VEGF drug). The patients were followed up for 6-20 months. The main efficacy indexes were the best corrected visual acuity, intraocular pressure, and retinal reattachment. Results The retina was completely reattached in 9 eyes and exudative retinal detachment was found in 2 eyes. At the end of follow-up, among the 11 cases, visual acuity was improved in 8 eyes, unchanged in 1 eye, decreased in 1 eye, and 1 case failed to cooperate with the examination. Strabismus occurred newly in 1 eye (the patient was young with poor eyesight) during the follow-up. No complications related to the operation were observed. Conclusion Transscleral subretinal fluid drainage and cryotherapy combined with intravitreal injection of anti-VEGF drug conbercept is an effective method for the treatment of stage 3 Coats disease, and it can achieve the retina reattachment in most patients and effectively rescue the visual function.