transplantation of retinal pigment epithelial (Rpe) sheets derived from human induced pluripotent cells (hipSc) is a promising cell therapy for Rpe degeneration, such as in age-related macular degeneration. current Rpe replacement therapies, however, face major challenges. they require a tedious manual process of selecting differentiated RPE from hiPSC-derived cells, and despite wide variation in quality of RPE sheets, there exists no efficient process for distinguishing functional RPE sheets from those unsuitable for transplantation. to overcome these issues, we developed methods for the generation of Rpe sheets from hipSc, and image-based evaluation. We found that stepwise treatment with six signaling pathway inhibitors along with nicotinamide increased RPE differentiation efficiency (RPE6iN), enabling the RPE sheet generation at high purity without manual selection. Machine learning models were developed based on cellular morphological features of f-actin-labeled Rpe images for predicting transepithelial electrical resistance values, an indicator of Rpe sheet function. Our model was effective at identifying low-quality RPE sheets for elimination, even when using label-free images. The RPE6iN-based RPE sheet generation combined with the non-destructive image-based prediction offers a comprehensive new solution for the large-scale production of pure Rpe sheets with lot-to-lot variations and should facilitate the further development of Rpe replacement therapies. Human pluripotent stem cells (hPSC) [human embryonic stem cells (hESC) and human induced pluripotent stem cells (hiPSC)] are valuable sources for regenerative therapies because of their capacity for self-renewal and pluripotency 1. Retinal regeneration using hPSC is a new promising treatment at the cutting edge of stem cellbased regeneration therapies. Retinal pigment epithelium (RPE) cells play important roles in vision and retinal function maintenance. Transplantation of RPE suspension or RPE sheets derived from hPSC for age-related macular degeneration (AMD) and Stargardt disease patients is considered safe and potentially effective 2-5. However, this treatment faces challenges regarding the purity and quality control of RPE products for transplantation therapy. The properties of cellular products are totally different from those of chemical drugs that are wellestablished in the synthesis and quality control of drug development.