We report, for the first time, the reliability issues of tunneling field-effect transistors (TFETs) by experiments. We observed that the overall reliability performance of n-TFETs is very different from those of the conventional n-MOSFET. The degradation of n-TFETs under positive bias temperature instability (PBTI) stress is very large compared with the negligible degradation for the conventional n-MOSFET. The degradation of n-TFETs under hot-carrier stress is also larger than that in the conventional n-MOSFET and has a different temperature dependence. The shifts of the I d- V g curves under PBTI stress are not parallel in the strong inversion region as in the case of the conventional n-MOSFET. The different degradation behaviors are explained by different degradation mechanisms due to some inherent properties of TFETs.