A portable navigation device with a TV function includes a TV module, a navigation module, a display module, a sound module, a first processing unit, a second processing unit and a TV command storage module. The TV module generates baseband TV signals, the navigation module generates position information, the display module displays image information, the sound module plays sounds, the first processing unit performs navigation programs, the second processing unit performs TV programs, and the TV command storage module stores TV commands from the first processing unit and the second processing unit. TV command transmission between the first processing unit and the second processing unit is achieved by sending interrupt signals or reset signals.