A portable device and a method for enabling the portable device are disclosed. The portable device comprises a power module, a processing module, a sensing module, and an enable control module. The power module is configured to provide electric power. The processing module is configured to run an operating system to drive the portable device when the processing module itself is enabled. The sensing module is configured to sense a gesture to generate a group of touch sensing signals, and to judge whether the group of touch sensing signals conform to a group of predefined signals so as to generate an operating system enabling signal. The enable control module is configured to temporarily enable the sensing module according to a switching signal, and to enable the processing module according to the operating system enabling signal.