Irrecoverable data destruction on a mobile device is important to prevent unintentional data disclosure. In this regard, transient electronics, a form of electronics that can be made to disappear or can be destroyed in a controllable manner, has been actively researched. To erase data completely, irreversible reactions such as physical or chemical destruction have been used. However, these techniques either require external voltage or destroy a memory device so that it cannot be reused. Here, we demonstrate a novel self-powered data-erasing method for nanoscale flash memory devices which uses triboelectricity via a kill switch, which consists of a nylon pad connected to a gate electrode of the flash memory. Through a one-time touch of the kill switch by a finger wearing a polytetrafluoroethylene (PTFE) glove, data stored in flash memory is set to the '1' state on the chip scale simultaneously with low-level triboelectricity, allowing the memory to be reused afterward. Moreover, the memory can be permanently destroyed by a single touch of the kill switch with a finger without a glove that generates high-level triboelectricity. These erase methods provide a rapid and convenient means of self-powered irrecoverable data erasing in the era of the Internet of Things (IoT).