A handheld device with switchable signal receiving modes includes a telescopic antenna, a telecommunication transceiver module, a satellite signal module, and a switch circuit. Upon receiving a switch signal, the switch circuit couples the telescopic antenna to the telecommunication transceiver module, and adjusts the telescopic antenna to a first length, so that the telecommunication transceiver module transmits and receives a signal of a first frequency, or the switch circuit adjusts the telescopic antenna to a second length, so that the telecommunication transceiver module transmits and receives a signal of a second frequency. Alternatively, the switch circuit couples the telescopic antenna to the satellite signal module, and adjusts the telescopic antenna to the second length, so that the satellite signal module receives a satellite signal. Thereby, the handheld device can receive signals of various frequencies via one antenna, so that different functional modules transmit and receive signals of different frequencies.