A near field communication method, for a near field communication system comprising at least one card reader and at least one mobile terminal equipped with a RF device, characterized in that the method comprises the following steps: step a, the card reader transmits low frequency alternating magnetic signals according to preset transmission parameters, the low frequency alternating magnetic signals carrying identification information of the card reader, the transmission parameters comprising a frequency for the low frequency alternating magnetic signal which is equal to or less than the highest working frequency f0 of the system at which the system needs not to be calibrated; step b, the RF device receives and detects the low frequency alternating magnetic signals on every distance point and amplifies them to voltage signals with constant amplitudes and corresponding to the distances, and thus determines whether the terminal equipped with the RF device enters a preset effective distance range using a preset voltage threshold Vt, wherein the voltage threshold Vt is the same for all terminals equipped with the RF device; step c, if the voltage corresponding to the received low frequency alternating magnetic signals is greater than or equal to the preset voltage threshold Vt, the terminal equipped with the RF device enters a preset effective range for swiping card, then the RF device acquires the identification information of the card reader from the received low frequency magnetic signals, and transmit it together with its own identification information to the card reader through the RF channel; step d, the card reader receives an information transmitted through the RF channel by the RF device, compares whether the identification information of the card reader in the above information is consistent with its own identification information; if it is, its own identification information is combined with the identification information of the RF device to act as a combined address, thus performing swiping transaction with the RF device through the RF channel. step a, the card reader transmits low frequency alternating magnetic signals according to preset transmission parameters, the low frequency alternating magnetic signals carrying identification information of the card reader, the transmission parameters comprising a frequency for the low frequency alternating magnetic signal which is equal to or less than the highest working frequency f0 of the system at which the system needs not to be calibrated; step b, the RF device receives and detects the low frequency alternating magnetic signals on every distance point and amplifies them to voltage signals with constant amplitudes and corresponding to the distances, and thus determines whether the terminal equipped with the RF device enters a preset effective distance range using a preset voltage threshold Vt, wherein the voltage threshold Vt is the same for all terminals equipped with the RF device; step c, if the voltage corresponding to the received low frequency alternating magnetic signals is greater than or equal to the preset voltage threshold Vt, the terminal equipped with the RF device enters a preset effective range for swiping card, then the RF device acquires the identification information of the card reader from the received low frequency magnetic signals, and transmit it together with its own identification information to the card reader through the RF channel; step d, the card reader receives an information transmitted through the RF channel by the RF device, compares whether the identification information of the card reader in the above information is consistent with its own identification information; if it is, its own identification information is combined with the identification information of the RF device to act as a combined address, thus performing swiping transaction with the RF device through the RF channel.