Policy hiatus is a specific type of policy change and policy succession, it means the phenomenon of initial policy may be terminated but similar policy still not to be reintroduced. And policy hiatus can occur in two ways: cyclical policy hiatus and one-off policy hiatus. Through the case study of reinstating collection of Securities Transactions Income Tax in Taiwan, this article explained the characteristics, causes and effects of policy hiatus, and got lesson-drawing from this experience. This article focused on the process of policy evolution and applied methods of literature review and legislative process analysis. It finds the characteristics of policy hiatus include cyclical hiatus, comet phenomenon, domino effect, policy orphan phenomenon. The factors such as incomprehensive policy planning, lack of policy leadership, issue attention deficit and formation of anti-reform coalition may cause. The effects includes: policy hiatus as signal of policy termination, policy decision dominated by legislative branch, the opportunity of reform shrunk, and violation the idea of policy reform. The future of policy hiatus may be succession or termination, but the experience of hiatus could increase the difficult of reform. The way of reducing appearance of policy hiatus is comprehensive planning, and don’t let policy hiatus be the way of blame-avoidance.