A magnetically controlled tire pressure monitoring apparatus includes a tire pressure detector, a power supply and a wake-up device. The power supply supplies electrical power to the tire pressure detector. The tire pressure detector includes a pressure sensor used to detect a tire pressure, a microcontroller connected to the pressure sensor and used to convert the tire pressure to a tire pressure value, a register connected to the microcontroller and used to store the tire pressure value or an ID code of the magnetically controlled tire pressure monitoring apparatus for data processing by the microcontroller, and a wireless signal transmitter connected to the microcontroller and used to convert the tire pressure value or the ID code to an electromagnetic signal. The wake-up device includes a reed switch connected to the microcontroller to control whether the wireless signal transmitter transmits the electromagnetic signal or not.