The equiboundedness of the solutions of ordinary and functional differential equations are mainly discussed by using Liapunov's second method. For a theorem on equiboundedness in ordinary differential equations in [V. Lakshmikantham and S. Leela, Math. Systems Theory, 10 (1976), 85-90], an example is presented. Moreover the theorem is extended to functional differential equations with infinite delay by using Liapunov-Razumikhin method, and an application is prp-sented.