The invention discloses a method for estimating the number of RFID devices, and the method comprises the steps that a card reading device determines a reference value, and sends the reference value toeach RFID device, so that the RFID device generates any random number in an estimation interval with the reference value as an upper limit; the card reading device polls each integer in the estimation interval and sends the integer to each RFID equipment, so that the RFID equipment responds to the received integer according to the random number generated by the card reading equipment; and the card reading device carries out parameter statistics according to the response message of the RFID equipment, and calculates the number of the RFID equipment according to the statistical parameter and the reference value after traversing each integer of the pre-estimation interval. The estimation method can effectively overcome the defect of manually setting the number of the RFID devices, and can accurately and efficiently estimate the number of the RFID devices. The invention further discloses card reading equipment and a computer readable storage medium which both have the above technical effects.