This paper focuses on the carbon emission reduction effect of anti-corruption mediated by renewable-led energy transition based on the panel data of 98 countries from 1996 to 2015. Since the mediation model is estimated by estimating a series of multiple regression equations, the total, direct and indirect effects can be separated out to clarify the conduction path between corruption control, renewable energy and carbon emissions. Owing to confirmation of the Sobel-Goodman mediation tests, renewable energy acts as a significant mediator through which corruption control contributes to emission reduction, regardless of the indicator is total carbon emissions, carbon emissions per capita or carbon emission intensity. For policymakers and regulators, there needs to be more emphasis on eliminating corruption in the increased penetration of renewable energy and not being seduced by traditional lobbyists. Particularly for developing countries, the effective way to reduce emissions is to remove institutional barriers in priority areas including the energy and resources sectors to cleaner-oriented energy transition.