A clothes drier comprises: a body; a drum rotatably installed at the body; a hot air supply unit configured to supply hot air into the drum; a heat exchanger configured to dehumidify air exhausted from the drum; a pipe unit configured to supply water to the heat exchanger and collect water from the heat exchanger; and a freeze damage preventing unit installed on the pipe unit. The clothes drier is provided with the freeze damage preventing unit configured to partially or completely discharge out water remaining in the heat exchanger after the clothes drier is stopped. Accordingly, freeze damage of the heat exchanger during winter time is prevented.