The invention discloses a printer paper quantity real-time monitoring system. A sensor module is mounted on a lifting assembly in each paper box of a printer and comprises an accelerometer chip, a microcontroller and a wireless chip, wherein the accelerometer chip senses the lifting variable quantity of the lifting assembly; the variable quantity is processed by the microcontroller to obtain paperquantity data; the paper quantity data is sent to a receiving module; the receiving module summarizes the paper quantity data and then transmits the summarized paper quantity data to a PC; and the PCdisplays the paper quantity in each paper box of the printer in real time and remotely monitors the paper quantity of the printer in real time. The printer paper quantity real-time monitoring systemhas the advantages of making up the defect that the traditional printer only gives out an alarm in the case of paper shortage, knowing the present paper quantity information and the like in the paperbox in real time and being simple and convenient to mount as the high value-added accessory of the printer.