This paper examines what factors are associated with the 2015 pension reform of Korean civil servant as social innovation. We explore what lessons we can learn from the pension reform in terms of the Advocacy Coalition Framework (ACF) model. The ACF model allows us to identify how the substantial reform is, relying on policy knowledge and entrepreneurs, possible in terms of political and social consensus. It also clearly demonstrates the possibility of systematic pension reform at an appropriate level through social learning and policy learning. Through the ACF model, we review how South