Gene therapy emerged as important approach in treatment for many inborn disorders caused by genetic defects, as well as other diseases. This manuscript focused on Adeno-associated virus (AAV) based gene therapy to eye diseases. The paper firstly introduced the AAV vectors and the techniques of eye delivery, then summarized some tested genes that were used in past treatment to retinal degeneration disorders. Finally the paper discussed the updated optogenetics and its roles in AAV based gene therapy for eye diseases.