Why do some democratic countries experience democratic breakdown, while others endure? Even though various potential factors behind democratic breakdown or survival have been widely examined, we still cannot fully explain the different fates of democratic regimes. This article sheds light on the role of the legacy of pro-democracy mass protest during the transition period in democratic survival of democratic regimes. Using cross-national time-series data on 135 democratic regimes in 103 democratic countries and the Cox Proportional Hazard model, we demonstrate that the legacy of prodemocracy mass protest decreases the hazard rate of democratic breakdown. This relationship is consistently robust in alternative model specifications. Moreover, our empirical results indicate that nonviolent pro-democracy mass protests compared to violent ones exert much more substantive deterrent impacts on democratic breakdown.