Positioning system for wireless monitoring of esophageal pH value, comprising: an internal transmitting apparatus, and an external recording apparatus; wherein, said internal transmitting apparatus comprises a pH sensor, a sample circuit, a first micro-processor, a power management unit, a first wireless transceiver module, and a first means; said external recording apparatus comprises a second micro-processor, a power management unit, a buzzer, a storage, a data interface, a key, a second wireless transceiver module, a status light, a housing, and a second means; and said second means of said external recording apparatus is configured to cooperate with said first means of said internal transmitting apparatus; and if said external recording apparatus detects that said internal transmitting apparatus is not in the preset region, said micro-processor is configured to control said buzzer and/or status light to alert; said external recording apparatus is configured to periodically detect the intensity of the signal received by said second wireless transceiver module, under the control of said micro-processor, and if it is detected that the signal intensity is not in the preset range of signal intensity, said micro-processor is configured to control said buzzer and/or said status light to alert; characterized in that said external recording apparatus further comprises temperature sensor; and said storage is configured to pre-store the first pH calibration data of said internal transmitting apparatus; and said temperature sensor is configured to detect the current room temperature, and to send the temperature data to said second micro-processor; and said second wireless transceiver module is configured to receive the initialized data from said internal transmitting apparatus and to send the data to said second micro-processor; and said second micro-processor is configured first to calibrate said initialized data, and to conduct temperature compensation in the course of calibration, in order to obtain the current calibration data; then to compare said current calibration data with said first pH calibration data pre-stored in said storage; and to send a calibration alerting signal to said internal transmitting apparatus through second wireless transceiver module if said current calibration data differ from said first pH calibration data; and said internal transmitting apparatus further comprises a work light; and said first wireless transceiver module of said internal transmitting apparatus is configured to receive said calibration alerting signal and send the signal to said first micro-processor; and said first micro-processor is configured to control said work light to alert. an internal transmitting apparatus, and an external recording apparatus; wherein, said internal transmitting apparatus comprises a pH sensor, a sample circuit, a first micro-processor, a power management unit, a first wireless transceiver module, and a first means; said external recording apparatus comprises a second micro-processor, a power management unit, a buzzer, a storage, a data interface, a key, a second wireless transceiver module, a status light, a housing, and a second means; and said second means of said external recording apparatus is configured to cooperate with said first means of said internal transmitting apparatus; and if said external recording apparatus detects that said internal transmitting apparatus is not in the preset region, said micro-processor is configured to control said buzzer and/or status light to alert; said external recording apparatus is configured to periodically detect the intensity of the signal received by said second wireless transceiver module, under the control of said micro-processor, and if it is detected that the signal intensity is not in the preset range of signal intensity, said micro-processor is configured to control said buzzer and/or said status light to alert; characterized in that said external recording apparatus further comprises temperature sensor; and said storage is configured to pre-store the first pH calibration data of said internal transmitting apparatus; and said temperature sensor is configured to detect the current room temperature, and to send the temperature data to said second micro-processor; and said second wireless transceiver module is configured to receive the initialized data from said internal transmitting apparatus and to send the data to said second micro-processor; and said second micro-processor is configured first to calibrate said initialized data, and to conduct temperature compensation in the course of calibration, in order to obtain the current calibration data; then to compare said current calibration data with said first pH calibration data pre-stored in said storage; and to send a calibration alerting signal to said internal transmitting apparatus through second wireless transceiver module if said current calibration data differ from said first pH calibration data; and said internal transmitting apparatus further comprises a work light; and said first wireless transceiver module of said internal transmitting apparatus is configured to receive said calibration alerting signal and send the signal to said first micro-processor; and said first micro-processor is configured to control said work light to alert.