We report the first example of photocatalytic acceptorless dehydrogenation using cationic Eosin Y as a bifunctional photocatalyst, without metal catalysts or HAT reagents. Under Bayesian optimized conditions, a wide range of flavones were synthesized in moderate to excellent yields, many of which were reported with biological activities. Mechanistic studies suggest that flavones likely form through two HAT processes, with hydrogen release occurring via photoredox.